Class 10

Punjab State Board PSEB 10th Class Hindi Book Solutions Chapter 11.ii अहसास Textbook Exercise Questions and Answers.

PSEB Solutions for Class 10 Hindi Chapter 11.ii अहसास

Hindi Guide for Class 10 PSEB अहसास Textbook Questions and Answers

(क) विषय-बोध

I. निम्नलिखित प्रश्नों के उत्तर एक-दो पंक्तियों में दीजिएप्रश्न

प्रश्न 1.
स्कूल बस पर छात्र-छात्राएँ कहाँ जा रहे थे?
उत्तर:
स्कूल बस पर छात्र-छात्राएँ शैक्षिक भ्रमण के लिए रोज़ गार्डन जा रहे थे।

प्रश्न 2.
छात्राएँ बस में क्या कर रही थीं?
उत्तर:
छात्राएँ बस में अंताक्षरी खेल रही थीं।

प्रश्न 3.
दिवाकर बस में बैठा क्या देख रहा था?
उत्तर:
दिवाकर बस में बैठकर खिड़की के बाहर वृक्षों को तथा दूर तक फैले आसमान को देख रहा था।

प्रश्न 4.
दिवाकर को अपने मन में अधूरेपन का अहसास क्यों होता था ?
उत्तर:
दिवाकर अपाहिज था और दूसरे बच्चों की भाँति उछल-कूद नहीं पाता था। इसलिए उसे अपने मन में अधूरेपन का अहसास होता था।

प्रश्न 5.
कार्यक्रम के दौरान छात्र-छात्राएँ क्या देखकर डर गए?
उत्तर:
कार्यक्रम के दौरान छात्र-छात्राएँ साँप को देखकर डर गए।

II. निम्नलिखित प्रश्नों के उत्तर तीन-चार पंक्तियों में दीजिए

प्रश्न 1.
दिवाकर की नए स्कूल में किसने मदद की?
उत्तर:
दिवाकर पिता की ट्रांसफर होने के कारण गाँव के स्कूल से शहर आया था। यहाँ शहर के स्कूल में वह स्वयं को अधूरा समझ रहा था। उसकी शारीरिक अपंगता उसे दूसरों से अलग करती थी। वह न ही उनके साथ खेल-कूद कर पाता था और न ही भाग-दौड़ पाता था। ऐसे समय में उसकी अध्यापिका नीरू ने अपने स्नेहपूर्ण व्यवहार से उसका हौसला बढ़ाया तथा समय-समय पर उसकी मदद भी की।

प्रश्न 2.
दिवाकर बैंच पर बैठकर क्या सोच रहा था?
उत्तर:
जिस समय सभी बच्चे रोज़ गार्डन में खेल-कूद रहे थे। झूला-झूल रहे थे। उस समय वहीं पास में एक बैंच पर बैठा दिवाकर अपनी पुरानी यादों में खोया हुआ था। वह दो साल पहले की घटना को याद कर, उसी में खोया था। उसे याद आता है कि दो साल पहले जब वह अपनी बड़ी मौसी के घर दिल्ली गया था तब उसने वहाँ फन सिटी में कितना मज़ा किया। उस समय फ़न सिटी में कितना खेला-कूदा था। वहाँ उसने खूब मस्ती की थी। यही सब विचार/ यादें उसके दिमाग में घूम रही थीं।

प्रश्न 3.
साँप को देखकर दिवाकर क्यों नहीं डरा?
उत्तर:
शहर में आने से पहले दिवाकर गाँव के स्कूल में पढ़ता था। वहाँ उसने खेतों में कई बार साँप और अन्य जानवरों को देखा था। उसके लिए साँप को देखना कोई नई और डर की बात नहीं थी। इसके साथ-साथ वह एक साहसी, निडर और कर्मशील बालक था। उसने अपनी सूझ-बूझ का परिचय देते हुए अपने विवेक और वैसाखी का सहारा लेकर सॉप को दूर फेंक दिया था।

प्रश्न 4.
दिवाकर ने अचानक साँप को सामने देखकर क्या किया?
उत्तर:
दिवाकर.अचानक साँप को देखकर तनिक भी घबराया नहीं जबकि अन्य छात्र-छात्राएँ डर के मारे काँप रहे थे। किसी को कुछ सूझ नहीं रहा था। ऐसे में दिवाकर ने बड़े ही धीरज से काम लिया। उसने बिना डरे और घबराए अपनी वैसाखी से साँप को उठाकर दूर फेंक दिया।

प्रश्न 5.
दिवाकर को क्यों पुरस्कृत किया गया?
उत्तर:
दिवाकर को जब उसकी साँप को वैसाखी से दूर फेंकने संबंधी वीरता, साहस एवं सूझ-बूझ के लिए प्रात:कालीन सभा में प्राचार्य महोदय द्वारा सम्मानित किया गया तो उस समय वह स्वयं को अधूरा अथवा अपाहिज न समझकर स्वयं को पूर्ण समझ रहा था। अब उसे दूसरों को देखकर स्वयं में कोई कमी का अहसास नहीं हो रहा था।

प्रश्न 6.
लघुकथा ‘अहसास’ का उद्देश्य क्या है?
उत्तर:
‘अहसास’ एक सामाजिक लघुकथा है। इसमें लेखिका ने एक बालक को शारीरिक चुनौतियों का सामना करते हुए दिखाया है। लेखिका प्रायः यथार्थ की पृष्ठभूमि पर अपनी कहानियों की रचना करती हैं। मानवतावाद का समर्थन करना ही उनका प्रमुख उद्देश्य रहा है। उनकी लघु कथा ‘अहसास’ शारीरिक चुनौतियों का सामना करने वाले बच्चों में आत्म-विश्वास जगाने वाली एक प्रेरणादायक लघुकथा है। लेखिका का विचार है कि समाज में शारीरिक अक्षमता को किसी की कमी न समझकर उसका हौसला बढ़ाना चाहिए। अपनी लघुकथा में लेखिका उद्देश्य को स्पष्ट करने में पूर्णतया सफल रही है।

प्रश्न 7.
‘अहसास’ नामकरण की सार्थकता स्पष्ट करो।
उत्तर:
कहानी का शीर्षक प्राय: कहानी के मूलभाव तथा उसकी प्रभावोत्पादक शक्ति का परिचायक होता है। शीर्षक सम्पूर्ण कहानी का निचोड़ होता है। यह कहानी की मूलभावना का प्रतीक होता है। प्रस्तुत कहानी का शीर्षक ‘अहसास’ है। यह शीर्षक अत्यंत आकर्षक, भावपूर्ण तथा जिज्ञासामय है। कहानी में दिवाकर जब प्रात:कालीन सभा में प्राचार्य द्वारा सम्मानित होता है तो उसे स्वयं में पूर्णता का अहसास होता है। उसके नीरस जीवन में सरसता का संचार हो जाता है। उसके मन का बदला यह भाव और अहसास ही कथा का शीर्षक बना है। इस प्रकार लघुकथा का शीर्षक उपयुक्त तथा अनुकूल है। सारी लघुकथा शीर्षक ‘अहसास’ से ही जुड़ी है तथा केंद्रित भी है।

(ख) भाषा-बोध

I. निम्नलिखित शब्दों के विशेषण शब्द बनाएँ

खामोश = ……………
व्यवहार = ………….
सम्मान = …………..
बहादुरी = …………..
रंग = ……………….
हिम्मत = ………………….
उत्तर:
खामोश = खामोशी
व्यवहार = व्यावहारिक
सम्मान = सम्मानित
बहादुरी = बहादुर
रंग = रंगीन
हिम्मत = हिम्मती

II. निम्नलिखित मुहावरों के अर्थ समझकर उनका वाक्यों में प्रयोग कीजिए

मुहावरा = अर्थ = वाक्य
i. चेहरे का रंग उड़ जाना = डर जाना = …………..
ii. पीठ थपथपाना = शाबास देना = ……………
iii. जान में जान आ जाना = राहत महसूस करना = ………………
उत्तर:
i. अपने कमरे में साँप को देखते ही रुचि के चेहरे का रंग उड़ गया था।
ii. पापा ने अनुज के परीक्षा में अंकों को देख पीठ थपथपाई थी।
iii. उस अंधेरी रात में घर पहुँच कर हम सबकी जान में जान आ गई थी।

(ग) रचनात्मक अभिव्यक्ति

‘प्रश्न 1.
आपने अपने सहपाठी की किसी प्रकार की मदद की हो तो अपने शब्दों में लिखिए।
उत्तर:
यह घटना पिछले वर्ष की है। हमारे विद्यालय में पारितोषिक वितरणोत्सव मनाया गया था। हमारी कक्षा में कई विद्यार्थी सांस्कृतिक कार्यक्रम प्रस्तुत करने के लिए चयनित हुए थे। उत्सव के दो दिन पहले मैं और मोहन हम दोनों विद्यालय से घर वापस जा रहे थे। तभी अचानक सड़क पार करते समय मोहन एक कार की चपेट में आ गया। उसके हाथ और पैर से खून निकल रहा था। मैंने तुरंत उसे उठाया और एक आटो रिक्शा में बैठा कर अस्पताल लेकर गया। वहाँ उसका इलाज करवाया। इसके बाद उसके माता-पिता को सारी घटना बताई। डॉक्टर ने कहा कि मैं सही समय पर मोहन को अस्पताल ले आया। यदि कुछ देर हो जाती तो उसकी जान पर खतरा बन सकता था। लेकिन मेरी सर्तकता और सूझ-बूझ के कारण उसकी जान बच गई।

प्रश्न 2.
अपने स्कूल के किसी शैक्षणिक भ्रमण का वर्णन अपने शब्दों में कीजिए।
उत्तर:
ऐतिहासिक स्थलों की यात्रा विद्यार्थियों के लिए बड़ी लाभप्रद है। ऐतिहासिक स्थलों पर पहुँच कर हम स्वयं, मानो इतिहास का अंग बन जाते हैं। इतिहास जीवित होकर मानों हमारे सामने साकार हो उठता है। ऐसी यात्राओं के द्वारा हम अपने इतिहास को सही दृष्टि से देखते हैं। ऐतिहासिक स्थलों तथा इतिहास के प्रति हमारे ज्ञान में वृद्धि के लिए हमारे विद्यालय से शैक्षणिक भ्रमण का आयोजन हुआ। हमारी यह यात्रा भारत की राजधानी की थी। हमारी उस ऐतिहासिक यात्रा का वर्णन निम्न प्रकार से है-
लाल किला-फरवरी मास में हमें अपने विद्यालय की ओर से दिल्ली की यात्रा के लिए ले जाया गया। हम पचास छात्र थे, हमारे साथ थे हमारे इतिहास के अध्यापक। हमने अपना सामान ‘क्लॉक रूम’ में रखा और नाश्ता करके हम लाल किला देखने चल पड़े। लाल पत्थर का यह किला शाहजहां ने बनवाया था ऐसा माना जाता है। दिल्ली से पहले मुग़लों की राजधानी आगरा थी। यह लाल किला मुग़ल वंश के इतिहास के साथ तो जुड़ा ही है, स्वतंत्र भारत के लिए भी इसका महत्त्व कम नहीं है।

नेता जी सुभाष की याद-लाल किले को देखकर नेता जी सुभाष चंद्र बोस की याद ताज़ा हो उठी। उन्होंने इसी किले पर अपने राष्ट्र’ का ध्वज फहराने का संकल्प किया था और अब हर वर्ष स्वतंत्रता दिवस को प्रधानमंत्री तिरंगा झंडा फहरा कर यहीं से राष्ट्र के नाम अपने संदेश प्रसारित करते हैं। आज़ाद हिंद सेना के वीरों पर मुकद्दमा भी इसी किले में चलाया गया था। अब यहाँ राष्ट्रीय अजायब घर है, जिसमें ऐतिहासिक महत्त्व की अनेक वस्तुएँ प्रदर्शित की गई हैं।

चाँदनी चौक और कुतुबमीनार-लाल किले के सामने चाँदनी चौक है। यह भी मुग़लों के समय का महत्त्वपूर्ण बाज़ार है। इसका महत्त्व अब भी कम नहीं हुआ है। यहाँ से हम बस में बैठ कर कुतुबमीनार पहुँचे। बहुत से इतिहासकारों का मत है कि कुतुबमीनार कुतुबद्दीन ऐबक द्वारा निर्मित करवायी गई थी, किन्तु कुछ अन्य इतिहासकार इसे एक भारतीय सम्राट् द्वारा निर्मित ध्रुवस्तंभ मानते हैं। उनके मतानुसार इसका निर्माण ज्योतिष शास्त्र के नियमों के अनुसार नक्षत्रों और ग्रहों का अध्ययन करने के लिए करवाया गया था। वे इसका संबंध कुछ दूरी पर बनी ‘जंतर मंतर’ नामक खुली वेधशाला से जोड़ते हैं जहाँ नक्षत्रों आदि की गति जानने के लिए काफ़ी विशद् प्रबंध किये गए हैं। ‘जंतर-मंतर’ को देखकर हम अपने पूर्वजों की वैज्ञानिक दृष्टि पर आश्चर्यचकित रह गए।

बिरला मंदिर-अब हम लोग बिरला मंदिर गए। इसी मंदिर में प्रार्थना सभा में राष्ट्रपिता महात्मा गाँधी की हत्या की गई थी। इस मंदिर को सभी संप्रदायों के देवताओं और महापुरुषों से संबंधित करके राष्ट्रीय एकता का प्रतीक बनाने की कोशिश की गई है। यहीं हमने भोजन भी किया।

राष्ट्रपति भवन-अब हम लोग संसद् भवन, सचिवालय तथा राष्ट्रपति भवन देखने गए। सौभाग्य से राष्ट्रपति भवन के मुग़ल-बाग दर्शकों के लिए खुले थे। इन्हें केवल फरवरी मास में ही खोला जाता है। असंख्य फूलों से भरे इस उपवन ने हमारे मन मोह लिए। सुंदर मोर और हिरण यहाँ-वहाँ घूम रहे थे। लगभग एक घंटा वहाँ रुकने के बाद हम होटल लौट आए।

राजघाट तथा शांति वन-कुछ देर आराम करने के पश्चात् हम राजघाट तथा शांति वन गए। यहाँ क्रमश: महात्मा गाँधी तथा जवाहरलाल नेहरू को श्रद्धांजलि अर्पित की। स्वर्गीय लालबहादुर शास्त्री की समाधि देखने विजयघाट भी गए। लौटते समय हम जामा मस्जिद भी गए। यहाँ से सभी लोग स्कूटरों पर बैठ कर कनाट प्लेस चले। दिल्ली का सारा सौन्दर्य शाम को वहाँ उमड़ आता है। यहाँ हमने टी हाउस में चाय पी थी। भीड़ को देखकर तो हम एकदम ही दंग रह गए। हम वहाँ अधिक देर नहीं ठहर सके, क्योंकि रात की गाड़ी से हमें लौटना भी तो था।

दिल्ली भारत का ही नहीं विश्व का एक प्रमुख शहर है। यहाँ अनेक दर्शनीय स्थान हैं। मैं समझता हूँ दिल्ली के भ्रमण के लिए कम-से-कम एक सप्ताह का कार्यक्रम बनाया जाना चाहिए।

(घ) पाठ्येतर सक्रियता

(I) 26 जनवरी गणतंत्र दिवस पर बहादुर बच्चों का वृत्तांत इंटरनेट पर देखें-उनकी बहादुरी के किस्सों को पढ़ें और अपने मित्रों को सुनाएं।
(II) शारीरिक चुनौतियों का सामना करने वाले उन महान चरित्रों की सूची बनाएँ-जिन्होंने अपने आत्म-विश्वास के बल पर चुनौतियों का सामना करते हुए अपने जीवन के मकसद को हासिल किया-उनमें हैलन-कैलर का नाम गर्व से लिया जाता है जो देखने, बोलने और सुनने में असमर्थ होने के बावजूद भी शिक्षा के उच्चतम शिखर पर पहुँची। इसी तरह ‘सुधा चंद्रन’ प्रसिद्ध नर्तकी-जिसकी एक दुर्घटना में टांग चली गई थी, ने अपनी मेहनत और विश्वास के बलबूते पर नृत्य के क्षेत्र में अपना मुकाम हासिल किया इसी तरह के अन्य चरित्रों के बारे में इंटरनेट से जानकारी प्राप्त करें।
उत्तर:
अपने अध्यापक/अध्यापिका की सहायता से स्वयं कीजिए।

(ङ) ज्ञान-विस्तार

‘अहसास’ लघुकथा जीवन में निरंतर संघर्ष करते रहने की प्रेरणा देती है। हमारे जीवन में अनेक कठिनाइयां आती रहती हैं, यदि हम उनसे घबरा कर हाथ पर हाथ रखे बैठ जाएंगे तो कभी भी उन्नति नहीं कर सकते। इसलिए मुसीबतों तथा कठिनाइयों का डट कर सामना करना चाहिए। अष्टावक्र आठ स्थानों से टेढ़े होते हुए भी अपनी विद्वता से सब को अपना लोहा मना सके। सूरदास, मिल्टन आदि अंधे होकर भी महान कवि बने। लुई ब्रेल ने अंधों के लिए ब्रेललिपि का आविष्कार कर उन्हें पढ़ने-लिखने का अवसर दिया। ऐसे ही अनेक उदाहरण दिए जा सकते हैं जो आत्मविश्वास, दृढ़ निश्चय, सही सोच तथा संघर्षरत रहकर हमें अपना लक्ष्य प्राप्त करने की प्रेरणा देते हैं। इसलिए ‘ईश्वर भी उनकी सहायता करता है, जो अपनी सहायता स्वयं करते हैं’ कथन के अनुसार पहल स्वयं ही करनी होगी। जब हम कर्म करने के लिए तत्पर हो जाते हैं तो हमारे साथ केवल हमारे दो हाथ ही नहीं परमात्मा के हज़ारों हाथ भी साथ होते हैं।

PSEB 10th Class Hindi Guide अहसास Important Questions and Answers

प्रश्न 1.
‘अहसास’ शीर्षक कहानी किस तरह की कहानी है?
उत्तर:
‘अहसास’ शीर्षक कहानी शारीरिक चुनौतियों का सामना करने वाले बच्चों में आत्म विश्वास जगाने वाली एक प्रेरणादायक लघुकथा है।

प्रश्न 2.
परीक्षा के तुरंत बाद किस कार्यक्रम का आयोजन हुआ?
उत्तर:
परीक्षा के तुरंत बाद शैक्षिक भ्रमण के आयोजन का कार्यक्रम निश्चित किया गया।

प्रश्न 3.
दिवाकर की टाँग कैसे टूट गई थी?
उत्तर:
पिछले वर्ष हुई एक दुर्घटना में दिवाकर की टाँग टूट गई थी।

प्रश्न 4.
दो वर्ष पहले दिवाकर कहाँ गया था? वहाँ उसने क्या किया था?
उत्तर:
दो वर्ष पहले दिवाकर अपनी बड़ी मौसी के घर दिल्ली गया था। वहां उसने फन सिटी में खूब मस्ती की थी।

प्रश्न 5.
सांस्कृतिक कार्यक्रम के दौरान लड़के और लड़कियाँ कहाँ बैठे थे?
उत्तर:
सांस्कृतिक कार्यक्रम के दौरान लड़के और लड़कियाँ वृक्षों के नीचे घर पर समूह बनाकर बैठे थे।

प्रश्न 6.
दिवाकर को अपनी पूर्णता का अहसास कैसे हुआ?
उत्तर:
प्रात:कालीन सभा में सम्मानित होने के बाद तालियों की गड़गड़ाहट में दिवाकर को अपनी पूर्णता का अहसास हुआ।

प्रश्न 7.
दिवाकर के लिए स्कूल नई जगह क्यों था?
उत्तर:
दिवाकर पहले गाँव के स्कूल में पढ़ता था। वह शहर के स्कूल में अभी कुछ दिन पहले ही आया था। इसलिए स्कूल उसके लिए नई जगह थी।

प्रश्न 8.
‘अहसास’ किस प्रकार की रचना है ? संक्षेप में बताइए।
उत्तर:
‘अहसास’ एक लघुकथा है। इसका कथानक अत्यंत छोटा है। छोटा कथानक होने के बावजूद इसका संदेश अत्यंत व्यापक एवं सटीक है। यह लघुकथा शारीरिक चुनौतियों का सामना करने वाले बच्चों में आत्म-विश्वास जगाने वाली प्रेरणादायक लघुकथा है।

प्रश्न 9.
लघुकथा ‘अहसास’ के आधार पर बताइए देश के सच्चे निर्माता कौन हैं?
उत्तर:
देश के सच्चे निर्माता देश के वे सभी लोग हैं जो अपने-अपने गांव-नगर में जन-सामान्य के प्रति मानवतापूर्ण व्यवहार करते हैं। वे प्रचार और प्रदर्शन की अपेक्षा चुपचाप दीन-हीन असहाय लोगों की सहायता करते हैं तथा उनका जीवन-स्तर ऊँचा उठाने में उनकी भरसक सहायता करते हैं। लघुकथा ‘अहसास’ में नीरू मैडम भी दिवाकर को समय समय पर हौसला तथा प्रेरणा देकर उसके जीवन को आगे बढ़ाने में उसकी सहायता करती हैं।

प्रश्न 10.
‘अहसास’ लघुकथा की भाषा-शैली पर प्रकाश डालिए
उत्तर:
प्रस्तुत लघुकथा की भाषा सरल तथा पात्रानुकूल है। आवश्यकतानुसार लेखिका ने अंग्रेजी के प्रचलित शब्दों-ट्रांसफर, स्कूल, रोज़-गार्डन, रिफ्रेशमैंट, सिटी आदि का प्रयोग किया है। भाषा विज्ञान की दृष्टि से इनका तत्सम शब्दों के प्रति विशेष लगाव है। इन्होंने यत्र-तत्र, विदेशी, तद्भव, देशज शब्दों का भी सहज रूप से प्रयोग किया है। इनकी भाषा में मुहावरों के प्रयोग से शक्ति वक्रता उत्पन्न हुई है।

एक पंक्ति में उत्तरात्मक प्रश्न

प्रश्न 1.
बेटे ने बसंती को पत्र में क्या लिखा था?
उत्तर:
उसकी तरक्की हो गई है और उसे कम्पनी की ओर से बहुत बड़ी कोठी मिली है, इसलिए वह उसके पास रहने के लिए आ जाए।।

प्रश्न 2.
बेटा माँ को नौकर के हवाले क्यों कर गया?
उत्तर:
बेटे की पत्नी काम पर तथा बच्चे स्कूल जा चुके थे।

प्रश्न 3.
स्कूल बस कहाँ के लिए रवाना हो चुकी थी?
उत्तर:
स्कूल बस एक दिवसीय शैक्षणिक भ्रमण के लिए रवाना हो चुकी थी।

प्रश्न 4.
दिवाकर को किसने हिम्मत दी?
उत्तर:
दिवाकर को कक्षा अध्यापिका नीरू मैडम के स्नेहपूर्ण व्यवहार ने हिम्मत दी।

बहुवैकल्पिक प्रश्नोत्तरनिम्नलिखित प्रश्नों के उत्तर एक सही विकल्प चुनकर लिखें

प्रश्न 1.
तालियों की गड़गड़ाहट में दिवाकर को अपनी किस बात का अहसास हो रहा था?
(क) अपूर्णता
(ख) पूर्णता
(ग) विजय
(घ) पराजय।
उत्तर:
(ख) पूर्णता

प्रश्न 2.
शहर में नौकरों वाला कमरा किसे दिया गया था?
(क) रोशमा को
(ख) बसंती को
(ग) बचनी को
(घ) भागो को।
उत्तर:
(ग) बचनी को

प्रश्न 3.
दिवाकर ने बैसाखी से किसे उठाकर दूर फेंक दिया?
(क) साँप को
(ख) कुत्ते को
(ग) चूहे को
(घ) बिल्ली को।
उत्तर:
(क) साँप को

एक शब्द/हाँ-नहीं/सही-गलत/रिक्त स्थानों की पूर्ति के प्रश्न

प्रश्न 1.
बसंती को जिस कमरे में ठहराया गया, वह उसे कैसा लगा? (एक शब्द में उत्तर दें)
उत्तर:
स्वर्ग

प्रश्न 2.
वह डरती-डरती बैड पर बैठ गई। (हाँ या नहीं में उत्तर दें)
उत्तर:
नहीं

प्रश्न 3.
दिवाकर वैशाखियों के सहारे चलता था। (हाँ या नहीं में उत्तर दें)
उत्तर:
हाँ

प्रश्न 4.
छात्राएँ लुकन-छिपाई खेल रही थीं। (सही या गलत में उत्तर दें)
उत्तर:
गलत

प्रश्न 5.
बेटे की ज़िद के आगे बसंती की एक न चली। (सही या गलत में उत्तर दें)
उत्तर:
सही

प्रश्न 6.
बहुत ……….. गदे थे।
उत्तर:
नर्म

प्रश्न 7.
नई ………… नए लोग।
उत्तर:
जगह

प्रश्न 8.
तुमने तो ………… कर दिया।
उत्तर:
कमाल।

अहसास कठिन शब्दों के अर्थ

अहसास = महसूस करना। भ्रमण = घूमना। फौरन = तुरंत। आसमा = आसमान। दिक्कत = परेशानी। अचानक = सहसा। पीठ थपथपाना = शाबाशी देना। निगाहें = नज़रें, दृष्टि। कमाल = एक दम अलग, अनोखा। प्रातः कालीन = सुबह का समय। प्राचार्य = प्रिंसीपल। चेहरे का रंग उड़ना = डर जाना। सम्मानित करना = आदर-सम्मान देना। पुरस्कृत करना = पुरस्कार देना। रिफ्रैंशमेंट = खाने के लिए कुछ देना। विकट = कठिन। सौहार्दपूर्ण व्यवहार = अच्छा एवं मधुर व्यवहार। रवाना होना = चले जाना। अन्ताक्षरी = एक प्रकार का संगीत से जुड़ा हुआ मनोरंजक खेल। शैक्षिक भ्रमण = शिक्षा संबंधी भ्रमण के लिए विद्यार्थियों का जाना।

अहसास Summary

अहसास लेखिका परिचय

जीवन परिचय-ऊषा० आर० शर्मा का जन्म 24 मार्च, सन् 1953 में मुंबई में हुआ था। इन्होंने भारत के विभिन्न राज्यों में अपने विद्यालय स्तर की शिक्षा प्राप्त की। पंजाब विश्वविद्यालय से दर्शन शास्त्र और लोक प्रशासन से एम० ए. की परीक्षा पास की। शिक्षा के प्रति इनका अत्यधिक लगाव था। इन्होंने शिक्षा विषय में स्नातक स्तर पर विशेष रूप से शिक्षा ग्रहण की। कई वर्षों तक इन्होंने भारतीय-प्रशासनिक सेवा (I.A.S.) की सदस्या के रूप में कार्य किया। इसके बाद वे शिक्षा और लेखन के क्षेत्र में निरंतर मार्गदर्शन का कार्य कर रही हैं। इनकी साहित्य और कला में गहरी रुचि थी। संगीत, नाटक तथा रंगमंच के कार्यक्रमों में भाग लेना इनकी इसी कला और प्रतिभा का साक्षात् उदाहरण है। पंजाब भाषा विभाग की ओर से इन्हें ज्ञानी संत सिंह पुरस्कार और सुदर्शन पुरस्कार दिए गए। इन्हें पंजाब साहित्य अकादमी के द्वारा ‘वीरेंद्र सारस्वत सम्मान’ प्रदान किया गया।

रचनाएँ-ऊषा आर० शर्मा बहुमुखी प्रतिभा की धनी हैं। इन्होंने विभिन्न विधाओं पर सफलतापूर्वक लेखनी चलायी है। इनकी प्रमुख रचनाएँ निम्नलिखित हैं-
एक वर्ग आकाश, पिघलती साँकलें, भोज पत्रों के बीच, दोस्ती हवाओं से, परिंदे धूप के, बूंद-बूंद अहसास, सूरज मेरा तुम्हारा और बीहड़ के फूल (सभी काव्य संग्रह) हाशिए पर बिंदु, क्यों न कहूँ आदि।
इनके कहानी-संग्रह, काव्य-संग्रह तथा कथा-संग्रह पर शोध कार्य का काम भी हो चुका है।

साहित्यिक विशेषताएँ-ऊषा आर० शर्मा जी ने गद्य एवं पद्य दोनों प्रकार की रचनाएँ लिखीं। ये लेखिका और कवयित्री के रूप में प्रतिष्ठित हुईं हैं। इनकी भाषा में तत्सम, तद्भव तथा विदेशी सभी प्रकार के शब्द मिल जाते हैं। उनकी शैली कवित्वपूर्ण, प्रेरणादायी एवं रोचक है। वे कम-से-कम शब्दों में छोटे-छोटे वाक्यों के माध्यम से अपनी बात कहने में सिद्धहस्त हैं।

अहसास कहानी का सार

‘अहसास’ ऊषा० आर० शर्मा द्वारा रचित एक लघुकथा है। इस कहानी में लेखिका ने शारीरिक चुनौतियों का सामना करने वाले एक अपाहिज बच्चे की कहानी द्वारा लोगों में एक अहसास जगाने का प्रयास किया है। विद्यालय में परीक्षाएँ समाप्त हो चुकी थीं। इसके तुरन्त बाद एक शैक्षिक भ्रमण का कार्यक्रम आयोजित किया गया। भ्रमण को लेकर बच्चों में गहरी रुचि थी। स्कूल बस में सभी के मन और तन हर्षित लग रहे थे। कोई अंताक्षरी खेल रहा था तो कोई मस्ती में झूम रहा था। लेकिन इन सबके बीच दिवाकर चुप-चाप, गुम-सुम सा बैठा हुआ था। वह बस की खिड़की से अंदर-बाहर देख रहा था। उसके पिता का ट्रांसफर हाल ही में हुआ था। पहले वह गाँव के स्कूल में पढ़ता था।

वह शारीरिक रूप से अपाहिज था। उसे वैशाखियों का सहारा लेकर चलना पड़ता था। उसकी अध्यापिका नीरू का व्यवहार तथा प्यार उसकी हिम्मत को बढ़ाता था। जल्दी ही रोज़ गार्डन आ गया। सभी छात्र-छात्राएँ खुशी से झूमते हुए पार्क में पहुँचे। पार्क में तरह-तरह के झूले थे। रंग-बिरंगे फूल खिले हुए थे। अध्यापिका नीरू बच्चों को रिफ्रेशमेंट बाँट रही थी। वहीं पास में दिवाकर एक बैंच पर बैठा हुआ था। वह अन्य छात्र-छात्राओं को झूला-झूलते हुए देख रहा था। उन्हें झूलते हुए देखकर उसे दो वर्ष पूर्व की घटना याद आ गई जब वह अपनी मौसी के घर दिल्ली गया था। उसने वहाँ फन सिटी में खूब मस्ती की थी। किंतु पिछले साल एक दुर्घटना में उसे अपनी टाँग खोनी पड़ी थी। अब वह स्वयं को अधूरा समझने लगा था।

तभी मैडम नीरू सभी बच्चों को साथ लेकर एक सांस्कृतिक कार्यक्रम करने लगी। दिवाकर वहीं पास के बैंच पर बैठा वह सब देख रहा था। सहसा एक साँप झाड़ियों में से निकल कर बच्चों के सामने आ गया। अपने सामने साँप को देखकर सभी छात्र-छात्राएँ और अध्यापिका डर गईं। किंतु ऐसी कठिन परिस्थिति में दिवाकर ने बड़ी ही सूझ-बूझ से काम लेते हुए अपनी वैशाखी से उस साँप को उठाकर दूर फेंक दिया। सभी की जान में जान आ गई। मैडम नीरू ने दिवाकर को शाबाशी देते हुए कहा-“दिवाकर। तुमने आज हम सबकी जान बचाई है। तुमने तो कमाल कर दिया। तुम वाकई बहादुर हो-असली हीरो।”

अगली सुबह विद्यालय की प्रार्थना सभा में प्राचार्य महोदय के द्वारा दिवाकर को उसकी सूझ-बूझ और वीरता के लिए सम्मानित किया गया। उस दिन दिवाकर को स्वयं में पूर्णता का अहसास हो रहा था।

Punjab State Board PSEB 10th Class English Book Solutions English Grammar Non-Finites Exercise Questions and Answers, Notes.

PSEB 10th Class English Grammar Non-Finites

(Answer Key has been given at the end of the exercises.)

Complete the following sentences, using the Infinitive form (with or without to) of the verbs given in brackets.

1. You are requested …………… me. (help)
2. She bade us ……………… away. (go)
3. I find the word ‘psychology difficult ………. . (spell)
4. Please make me …………… why the stars twinkle. (understand)
5. The medicine is too bitter …………. (take)
Answer:
1. to help
2. go
3. to spell
4. understand
5. to take.

Replace the Relative Clause in each of the following sentences by an Infinitive.

Example : You have some important work which you must finish.
Answer :
You have some important work to finish.

1. You have a train that can carry you back home.
2. She wants something that she can drink.
3. They advised me that I should see an eye specialist.
4. Mohan had no proof that he could show.
5. I gave him a book that he could consult.
6. Asha is not a servant who can be trusted.
Answer:
1. You have a train to carry you back home.
2. She wants something to drink.
3. They advised me to see an eye specialist.
4. Mohan had no proof to show.
5. I gave him a book to consult.
6. Asha is not a servant to be trusted.

Rewrite the following sentences, using an Infinitive.

1. I would be happy if I could join this company. (to join).
2. At Agra, we have the Taj that one can visit.
3. His handwriting is so bad that one cannot read it…
4. Papa was angry when he found that his glasses were broken.
5. I was shocked when I heard of the terrible accident.
6. I will tell him that he should post the letter today.
Answer:
1. I would be happy to join his company.
2. At Agra, we have the Taj to visit.
3. His handwriting is too bad to read.
4. Papa was angry to find that his glasses were broken
5. I was shocked to hear of the terrible accident.
6. I will tell him to post the letter today.

Combine the following pairs of sentences, using a Present Participle or a Past Participle. Treat the first two sentences as examples.

1. I felt sorry for the blind man. I gave him a hundred-rupee note.
2. My uncle arrived. He was accompanied by Mohan.
3. We found the child. It was crying for its father.
4. He raised his sword. He struck his enemy.
5. I heard the bang. I sprang up from my bed.
6. He broke his leg. It made it difficult for him to walk.
7. The child was lost. He found no joy in the fair.
Answer:
1. Feeling sorry for the blind man, I gave him a hundred
2. Accompanied by Mohan, my uncle arrived.
3. We found the child crying for its father.
4. Raising his sword, he struck his enemy.
5. Hearing the bang, I sprang up from my bed.
6. Having broken his leg, it became dificult for him to walk
7. The lost child found no joy in the fair.

Combine the following sets of sentences, using a Non-finite verb (Infinitive, Gerund, or Participle).

1. I enjoyed the mangoes. These were sent by my uncle.
2. We go to the library. We read books there.
3. I am happy. I accept your invitation.
4. He took his gun. He fired at the bird.
5. She left home early. She arrived here on time.
6. He wants to marry Mary. His father is opposed to this.
7. Mohan sells apples. He earns fifty rupees a day.
8. It was an extremely cold day. I could not work at all. (Start with : It being ……….)
9. They held a meeting. They discussed the matters of the school.
10. I went to the Headmaster. I sought a favour.
Answer:
1. I enjoyed the mangoes sent by my uncle.
2. We go to the library to read books.
3. I am happy to accept your invitation.
4. Taking his gun, he fired at the bird.
5. Leaving her home early, she arrived here on time
6. His father is opposed to his marrying Mary
7. Selling apples, Mohan earns fifty rupees a day
8. It being an extremely cold day, I could not work at all. Go
9. They held a meeting to discuss the matters of the school.
10. I went to the Headmaster to seek a favour.

Fill in the blanks with suitable Non-finites (Infinitive, Gerund or Participle).

1. I am afraid of ……………… in the court. (appear)
2. ………………. thieves in her house, she started …………. (see, shout)
3. He decided ……….. his income by ……. a private tuition. (increase, take)
4. I noticed your friend …………. with a gambler. (sit)
5. It is easier …………. than ……….. (say, do)
6. Do you want ……….. my address ? (know)
7. Every miser hates …………. money. (spend)
8. They were eager ……….. the game. (start)
9. This rent is quite reasonable for a well …………. house. (furnish)
10. The children seemed ………….. on seeing the giant. (frighten)
Answer:
1. appearing
2. Seeing, shouting
3. to increase, taking
4. sitting
5. to do
6. to know
7. spending
8. to start
9. furnished
10. frightened.

Combine the following sets of sentences into a single sentence each.

1. Mohan is trying. He wants to follow Gandhiji.
2. The Chairman tried it. He wanted to put him off.
3. Mohan did not look at the girls. He avoided it.
4. The old man took the trouble of it. He explained the matter in detail.
5. It is no use. Don’t cry over spilt milk.
6. Hari does not accept bribes. He hates it.
7. You should not blow horn near a hospital. It is forbidden.
8. He stole the ornaments. He looked for a place to hide them.
9. I saw a gentleman. He was sitting next to me.
10. He stood aside. He was waiting for orders.
Answer:
1. Mohan is trying to follow Gandhiji.
2. The Chairman tried to put him off.
3. Mohan avoided looking at the girls.
4. The old man took the trouble of explaining the matter in detail
5. It is no use crying over spilt milk
6. Hari hates accepting bribes.
7. It is forbidden to blow a horn near a hospital.
8. Having stolen the ornaments, he looked for a place to hide them.
9. I saw a gentleman sitting next to me.
10. Standing aside, he was waiting for orders.

यदि कोई क्रिया कर्ता के वचन (number) और पुरुष (person) के प्रभाव से मुक्त हो तो उसे Non-finite Verb कहा जाता है; जैसे

1. I want to dance.
2. She wants to dance.
3. They want to dance.
4. Radha wants to dance.
ऊपर दिए गए वाक्यों में क्रिया dance पर कर्ता का कोई प्रभाव नहीं पड़ा है। इसलिए इसे Non-finite (असीमित अर्थात् बिना बन्धन) क्रिया कहा जाता है।

Non-finites तीन प्रकार के होते हैं

1. The Infinitive
(a) Bare Infinitive
(b) To-infinitive.

2. The Gerund
3. The Participle
(a) Present Participle
(b) Past Participle
(c) Perfect Participle.

Bare Infinitive का प्रयोग

Bare Infinitive (to के बिना infinitive) का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. निम्नलिखित सहायक क्रियाओं (Modal Auxiliaries) के बाद :
do, does, did, can, could, will, would, shall, should, may, must, might, need, dare.
1. He may come today.
2. I shall accompany you.
3. I can play cricket.
4. You need not do it.
5. She dare not come here.

नोट : need और dare का प्रयोग जब मुख्य क्रियाओं के रूप में किया गया हो तो इनके साथ to- infinitive का प्रयोग किया जाता है; जैसे
1. He didn’t dare to come here.
2. You don’t need to go there.

नोट : सहायक क्रियाओं ought और used के बाद भी to-infinitive का प्रयोग किया जाता है; जैसे
1. You ought to finish your work.
2. He used to come here daily.

2. निम्नलिखित सकर्मक (Transitive) क्रियाओं के बाद :
make, let, bid, feel, hear, see, watch, notice, observe, आदि क्रियाओं के बाद bare infinitive का प्रयोग किया जाता है जब ये क्रियाएँ Active Voice में हों; जैसे
1. I saw him steal my pen.
2. I heard him go up the stairs.
3. I felt the cold air strike against my face.
किन्तु hear, make तथा see का प्रयोग जब Passive Voice में किया गया हो तो इनके बाद to-infinitive का प्रयोग किया जाता है; जैसे

1. He was heard to say all this.
2. She was made to dance.
3. He was seen to enter the office.
नोट : feel, hear, see तथा watch के बाद प्रायः -ing वाली क्रिया अर्थात् Present Participle का प्रयोग भी किया जाता है; जैसे

1. I saw him leaving the office. (Active)
2. He was seen leaving the office. (Passive)
3. I heard her shouting at him. (Active)
4. She was heard shouting at him. (Passive)

3. had और would वाले निम्नलिखित phrases के बाद : had better, had rather, would rather, had sooner, would sooner.

1. I would rather die than beg.
2. You had better stop smoking.

4. than, but तथा except के बाद जब इनका प्रयोग conjunction के रूप में किया गया हो; जैसे
1. He did nothing but laugh.
2. I could do nothing except agree to it.
3. I would rather walk than ride your scooter.
नोट : but के बाद bare-infinitive का प्रयोग केवल तभी किया जाता है जब but से पूर्व मुख्य क्रिया के रूप में do, does अथवा did का प्रयोग किया गया हो।

To-infinitive का प्रयोग

To-infinitive का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. ought और have के बाद to-infinitive का प्रयोग किया जाता है यदि इन शब्दों का प्रयोग किसी ज़िम्मेदारी (obligation) अथवा कर्त्तव्य को प्रकट करने के लिए किया गया हो। सहायक क्रिया used के बाद भी to-infinitive का प्रयोग किया जाता है; जैसे

1. We ought to help the poor.
2. You ought to respect your elders.
3. Boys had to pay their fees.
4. I have to support my family.
5. She has to live with her parents.
6. She used to come here daily.

नोट : ought और used के अतिरिक्त शेष सभी Modals के साथ bare-infinitive का प्रयोग किया जाता है।

2. निम्नलिखित क्रियाओं के साथ to-infinitive लगाया जाता है यदि इनका प्रयोग किसी मनोरथ, इच्छा अथवा तत्परता को प्रकट करने के लिए किया गया हो
want, hope, like, love, hate, promise, intend, propose, decide, swear, learn, remember, forget, agree, consent, neglect, refuse, attempt, fail, hesitate, prepare, care, pretend, determine, arrange, seem.

1. I want to go now.
2. She decided to marry him.
3. I forgot to answer this question.
4. They promised to pay all the taxes.

3. निम्नलिखित सकर्मक (transitive) क्रियाओं के साथ object लगाने के बाद to-infinitive का प्रयोग किया जाता है
ask, advise, allow, beg, compel, encourage, force, instruct, invite, order, permit, request, tell, teach, warn, आदि।

1. I begged him to help me.
2. My mother asked me to work hard.
3. The teacher allowed him to go.
4. The boys requested the teacher to forgive them.

4. किसी कारण अथवा उद्देश्य को प्रकट करने के लिए भी to-infinitive का प्रयोग किया जाता है; जैसे

1. She came here to consult you.
2. I went to Delhi to meet my brother.
3. They stopped at the market to buy some apples.

5. जब किसी क्रिया को कर्ता के रूप में प्रयोग किया गया हो, तो भी to-infinitive का प्रयोग किया जाता है; जैसे
1. To tell lies is a bad thing.
2. To play with fire is dangerous.
3. To kill little birds is a sin.

6. यदि किसी क्रिया का प्रयोग object के रूप में किया जा रहा हो, तो भी to-infinitive का ही प्रयोग किया जाता है; जैसे
1. I want to go now.
2. She hopes to pass this year.

7. किसी क्रिया के पूरक (complement) के रूप में to-infinitive का प्रयोग किया जाता है; जैसे
1. His aim was to get good marks.
2. My hobby is to collect stamps.
3. They were to reach here today.

8. किसी noun की विशेषता प्रकट करने के लिए; जैसे
1. This cloth is easy to wash.
2. This question is difficult to do.

9. too + adjective / adverb के बाद नकारात्मक अर्थ के लिए; जैसे
1. He is too weak to walk.
2. He was too drunk to drive home.
3. She walked too slowly to catch the train.

10. adjective / adverb + enough के बाद सकारात्मक अर्थ के लिए; जैसे
1. He is rich enough to buy a car.
2. She is old enough to travel by herself.
3. This bag is light enough for me to carry.
4. She jumped high enough to touch the ceiling.

11. यदि किसी ordinal number (first, second, last, आदि) का प्रयोग एक विशेषण के रूप में किया
गया हो तो इसके बाद to-infinitive का प्रयोग किया जाता है। जैसे
1. I was the first to reach there.
2. Radha was the last to leave the class.

12. how, when, where, what, आदि शब्दों के बाद object के रूप में to-infinitive का प्रयोग किया जाता है; जैसे
1. I do not know how to swim.
2. He did not know what to do.
3. Can you tell me where to go ?
4. How can I say when to leave ?

13. It + is/was + adjective + for/ of + noun / pronoun to-infinitive का प्रयोग
1. It is easy for you to say that.
2. It was kind of him to help us.
3. It was brave of Ram to catch the thief.
4. It is difficult for Mohan to finish that work alone.

14. यदि किसी क्रिया का प्रयोग किसी adjective के बाद एक object के रूप में किया गया हो, तो to-infinitive का प्रयोग किया जाता है; जैसे
1. I am happy to see you here.
2. It is bad to abuse others.
3. It is good to finish the work in time.

15. यदि किसी क्रिया का प्रयोग किसी noun या pronoun की व्याख्या करने के लिए किया गया हो, तो भी to-infinitive का प्रयोग किया जाता है; जैसे
1. I have some letters to write.
2. I want some bread to eat.
3. He has a machine to wash the clothes.

Rewrite adding ‘to’ where necessary before the Infinitives in brackets.

1. Mohan wants …………… (swim) in the river.
2. …………….. (kill) a man is a crime.
3. Mihir Sen wanted ………….. (swim) the English Channel.
4. Let him ……………. (go) now.
5. I have come …………… (see) the Principal.
6. It began …………….. (rain) and we couldn’t ……………. (go) out.
7. We saw him …………… (arrive) at the station.
8. The book was easy ……………. (read).
9. We didn’t …………… (expect) Rama . …………. (win).
10. They heard her ………….. (sing).
11. Mohan knows how …………. (answer) the question.
12. He was too tired ……………. (walk).
13. He made me …………….. (do) it.
14. They stopped …………….. (have) some rest.
15. He is saving money …………….. (buy) a scooter.
Answer:
1. to swim
2. To kill
3. to swim
4. go
5. to see
6. to rain, go
7. arrive
8. to read
9. expect, to win
10. sing
11. to answer
12. to walk
13. do
14. to have
15. to buy.

Use the verbs in brackets with or without ‘to’ to complete each sentence.

1. He is too weak (walk).
2. It is easy (make) mistakes.
3. Who is (blame) in this ?
4. This dress is good (wear).
5. Do you want (see) this film ?
6. I saw him (open) the door.
7. This cloth is easy (wash).
8. You ought (obey) your parents.
9. We don’t allow anyone (smoke) in this room.
10. The thief was seen (enter) the building.
11. She did not let me (enter) her room.
12. I made him (give) my money back.
13. I wanted (help) him but I could not (meet) him.
14. How dare you (open) my letter ?
15. I would rather (die) than (beg).
Answer:
1. to walk
2. to make
3. to blame
4. to wear
5. to see
6. open
7. to wash
8. to,obey
9. to smoke
10. enter
11. enter
12. give
13. to help, meet
14. open
15. die, beg.

Rewrite adding ‘to’ where necessary before the Infinitives in brackets.

1. I can (sing) quite well.
2. You needn’t (say) anything.
3. He made me (repeat) words.
4. He will be able (swim) very soon.
5. Would you like (come) with me?
6. I know he won’t (tell) the truth.
7. It is easy (find) fault with others.
8. You ought (go) today; he may (go) tomorrow.
9. How dare you (speak) to me like this?
10. Can you help me (move) this table ?
11. Visitors are requested (not feed) the animals in the zoo.
12. He tried (make) me a fool.
13. Did you hear the cock (crow)?
14. There is nothing (do) now.
15. I am sorry (disturb) you.
Answer:
1. sing
2. say
3. repeat
4. to swim
5. to come
6. tell
7. to find
8. to go, go
9. speak
10. move
11. not to feed
12. to make
13. crow.
14. to do
15. to disturb.

The Gerund

क्रिया के ऐसे -ing वाले रूप को Gerund कहा जाता है जो किसी noun का काम कर रहा हो। इसके विभिन्न प्रयोग निम्नलिखित हैं

1. किसी क्रिया के Subject के रूप में; जैसे
1. Smoking causes cancer.
2. Swimming improves one’s health.

2. किसी क्रिया के Object के रूप में; जैसे
1. I love swimming.
2. I dislike smoking.

3. किसी Preposition के Object के रूप में; जैसे
1. He is fond of playing.
2. She was fined for coming late.

4. क्रिया ‘be’ के पूरक (complement) के रूप में; जैसे:
1. His only aim was cheating.
2. My favourite hobby is gardening.

5. किसी pronoun के समान-अधिकरण के रूप में; जैसे
1. It is no use crying.
2. It is foolish saying that.

6. निम्नलिखित शब्दों या शब्द-समूहों के बाद
No, busy, worth, be used to, object to, It is no use.

1. No smoking in the hall.
2. No parking here, please.
3. I am busy doing my homework.
4. This book is worth buying.
5. She is used to telling lies.
6. I am used to living a hard life.
7. I object to writing on my walls.
8. She objected to dancing in her house.
9. It is no use crying over spilt milk.
10. It is no use waiting for her now.

7. निम्नलिखित क्रियाओं के बाद object के रूप में to-infinitive तथा gerund में से किसी का भी प्रयोग किया जा सकता है
advise, allow, attempt, begin, continue, hate, intend, learn, like, love, remember, start, आदि

To-infinitive	Gerund
1. He intends to live here. 2. I love to hear this song. 3. I remembered to see him. 4. We prefer to travel by air. 5. He continued to write letters.	1. He intends living here. 2. I love hearing this song. 3. I remembered seeing him. 4. We prefer travelling by air. 5. He continued writing letters.

8. निम्नलिखित क्रियाओं के साथ bare infinitive अथवा gerund में से किसी का भी प्रयोग किया जा सकता है
feel, hear, notice, observe, see, watch, आदि।

Bare Infinitive	Gerund
1. I heard her come in. 2. She saw me cross the road. 3. I heard you shout in the class.	1.  I heard her coming in 2.  She saw me crossing the road. 3. I heard you shouting in the class.

9. निम्नलिखित क्रियाओं के साथ केवल gerund का प्रयोग किया जाता है। इनके साथ infinitive का प्रयोग कभी नहीं किया जाना चाहिए|
avoid, delay, deny, dislike, enjoy, finish, forget, keep (जारी रखना), mind (बुरा मानना), imagine, pardon, postpone, risk, stop, suggest, try (परखना), understand.
1. Please stop writing.
2. I dislike telling lies.
3. Please pardon my saying so.
4. Don’t risk going out in the storm.
5. I avoid meeting such persons.

10. निम्नलिखित शब्दों के साथ भी केवल gerund का ही प्रयोग किया जाता है
be worth, can’t bear, be no use, can’t stand, be no good, can’t help.
1. This table is worth buying.
2. It is no good imitating others.
3. It is no use crying over spilt milk.
4. She can’t bear living away from her children.
5. We couldn’t help laughing at him. (रोक न सकना)
6. I can’t stand smoking in my room. (सहन न कर सकना)

11. यदि mind शब्द का प्रयोग क्रिया के रूप में किया गया हो तो उसके बाद object के रूप में gerund का प्रयोग किया जाना चाहिए; जैसे
1. I don’t mind spending on books.
2. Would you mind sitting on the floor ?
3. Do you mind closing the window ?

12. किसी सम्बन्धवाचक संज्ञा या सर्वनाम के बाद सदा gerund का ही प्रयोग किया जाता है; जैसे
1. Do you mind my smoking here?
2. I dislike Mohan’s coming late daily.
3. Your future depends on your working hard.

13. Need और want के साथ gerund का प्रयोग passive अर्थ में होता है; जैसे
1. My hair wants cutting (needs to be cut).
2. Your dress needs repairing (needs to be repaired).

14. यदि try शब्द के बाद infinitive का प्रयोग किया गया हो तो इस का अर्थ होता है – ‘प्रयत्न करना’
Try के बाद यदि gerund का प्रयोग हो तो इस का अर्थ होता है – ‘प्रयोग करना’ या ‘प्रयोग कर देखना’; जैसे
1. I tried to sleep, but couldn’t.
2. If you cannot sleep, try taking a sleeping pill.

15. Like के बाद यदि gerund का प्रयोग होता हो, तो उसका अर्थ होता है ‘आनन्द उठाना’।
Like के बाद यदि infinitive का प्रयोग हो, तो उसका अर्थ होता है-‘चाहना’, ‘सहमत होना’, ‘पसंद करना’, आदि; जैसे
1. I like swimming ( = I enjoy swimming).
2. I didn’t like to disturb her as she was sleeping.

किन्तु dislike के बाद सदा gerund का ही प्रयोग किया जाता है।
1. I disliked disturbing her as she was sleeping.
2. I disliked swimming in the muddy river.

Fill in the blanks with the correct form (Gerund or Infinitive) of verbs given in brackets.

1. I enjoyed………… (swim) in the river.
2. I want them ……………… (come) back soon.
3. The thief attempted …………. (escape) but he was caught.
4. The boys suggested …………. (go) for a picnic.
5. My grandmother dislikes …………. (use) face powder.
6. Don’t you remember ………… (see) her at Mohan’s birthday party ?
7. You must remember ……….. (telephone) me after ……….. (reach) there.
8. How long do you expect …………… (stay) in Agra ?
9. ……………. (learn) English quickly is not an easy thing.
10. She promised ……….. (return) it as soon as possible.
11. This problem is difficult ………….. (solve).
12. I wanted ………….. (suggest) it, but I was afraid of ……… (offend) her.
13. It is very easy …………. (criticize) other people’s work.
14. ………… (write) good essays is very difficult.
15. This book is not worth ……….. (buy).
Answer:
1. swimming
2. to come
3. to escape
4. going
5. using
6. seeing
7. to telephone,reaching
8. to stay
9. Learning
10. to return
11. to solve
12. to suggest, offending
13. to criticize
14. Writing
15. buying.

The Participle

क्रिया के जिस रूप में Verb तथा Adjective दोनों के गुण हों, उसे Participle कहा जाता है। Participles तीन प्रकार के होते हैं

Present Participle (V1 -ing)	Past Participle (V3)	Perfect Participle (having + V3)
Seeing	Seen	Having seen
Drowning	Drowned	Having drowned
Finishing	Finished	Having finished

1. Present Participle उदाहरण
1. The results were encouraging.
2. A drowning man catches at a straw.
3. Seeing the police, the thief ran away.
4. Naresh went into the bathroom singing.

2. Past Participle of उदाहरण
1. I saw a faded rose.
2. I boarded a crowded bus.
3. These solved papers are very helpful.
4. His spoken English is much better than yours.

3. Perfect Participle के उदाहरण
1. Having won a prize, Neelu felt happy
2. Having done his homework, John went out to play.
3. Having bought a book, I came back from the market.
4. Having attended a meeting of the club, I came back.

Present Participle का प्रयोग 

Present Participle का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. Continuous Tense बनाने के लिए; जैसे____

1. He is writing a letter.
2. She was sleeping in her room.
3. It will be raining on the hills.

2. एक Adjective (विशेषण) के रूप में; जैसे
1. I saw a burning house.
2. Barking dogs seldom bite.
3. He told me an interesting story.

3. किसी Subject के पूरक (complement) के रूप में; जैसे
1. The girl was charming.
2. The work was tiring.
3. The play was boring.

4. Object के पूरक के रूप में, जैसे
1. I found her sleeping:
2. I saw him running.
3. We heard the bombs exploding.

5. जब कोई क्रिया वाक्य की मुख्य क्रिया के समय पर ही हो रही हो; जैसे
1. She went away laughing.
2. The girls entered the stage singing a song.
3. Looking through some old papers, I came across this letter.
I looked through some old papers and came across this letter.
4. Seeing the Headmaster, the students stopped talking.
The students saw the Headmaster and they stopped talking.

6. जब कोई कार्य मुख्य क्रिया का ही भाग हो या उसका परिणाम हो; जैसे
1. He fired, killing the tiger.
2. She went away, breaking my heart.
3. It rained heavily, flooding the rivers
4. The police fired, killing two thieves.

7. It + be + Present Participle + infinitive की रचना वाले वाक्यों में जैसे
1. It was depressing to find him sick.
2. It is boring to do the same thing every day.

8. have + object के बाद जैसे
1. He had people waiting for him all day.
2. I won’t have him sleeping in my room,

9. see / hear / feel / smell / watch / notice + object के बाद जैसे
1. I felt the earth moving.
2. I saw him passing my house.
3. She smelt something burning.
4. I watched them rehearsing the play.
5. Didn’t you hear the children shouting ?

10. catch / find / leave + object के बाद जैसे
1. He left me crying in pain.
2. I caught him stealing my books.
3. I found him standing at the door.

11. go तथा come के बाद शरीर सम्बन्धी क्रिया ओं के लिए जैसे –
1. She came dancing / crying / shouting / etc.
2. They went swimming / hunting / riding / shopping / etc.

12. spend / waste + समय या धन सम्बन्धी वर्णन के बाद जैसे |
1. He spends two hours a day swimming.
2. He spent a lot of money buying gifts for her.
3. He wasted a whole afternoon trying to repair his car.

13. be + busy के बाद जैसे
1. I am busy doing my homework.
2. She was busy packing her luggage.

Past Participle का प्रयोग

Past Participle का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. Perfect Tense बनाने के लिए; जैसे
1. Ram has gone to Shimla.
2. I have finished my work.
3. She had written the poem.

2. विशेषण के रूप में; जैसे
1. I saw a wounded bird.
2. They don’t admit failed students.

3. Subject के पूरक के रूप में; जैसे
1. The corrupt officer was dismissed.
2. All the schools were closed.

4. Object के पूरक के रूप में; जैसे
1. I found the books stolen.
2. They left the work unfinished.

5. Adverb के रूप में; जैसे
1. He went away greatly satisfied.
2. He left the hospital cured.

6. दो वाक्यों को जोड़ने के लिए; जैसे
A speeding car hit him. He died on the spot.
= Hit by a speeding car, he died on the spot.

Perfect Participle का प्रयोग

1. He milked the cow. Then he went to market.
= Having milked the cow, he went to market.

2. He finished his work. Then he went home.
= Having finished his work, he went home.

3. He completed his studies. Then he started looking for a job.
= Having completed his studies, he started looking for a job.

Use the correct non-finite form (Infinitive, Gerund or Participle) of the given- verbs.

1. The rice will grow well in the (come) season.
2. We heard of his (come) back today.
3. We hope (see) him back soon.
4. (believe) him to be right, I trusted him.
5. Night (come) on, the men went home.
6. Did you hear of his (win) a prize ?
7. I am tired of (do) this work.
8. Generally (speak), we get what we deserve.
9. We saw him (leave) the house.
10. I was very happy (see) you.
11. I shall be glad (help) you.
12. My wife (expect) my return, did not leave the house.
Answer:
1. go
2. to smoke
3. to accept
4. telling
5. polish
6. crying
7. going
8. taking
9. Swimming
10. to stay
11. living
12. to meet.

Put the verbs in brackets into the correct Non-finite form.

1. Please let me (go) now.
2. He used (smoke) too much.
3. He refused (accept) the bribe.
4. My dad hates (tell) lies.
5; He made me (polish) his shoes.
6. It is no use (cry) over spilt milk.
7. He is used to (go) to cinema too often.
8. She objected to (take) her bicycle.
9. (swim) is a good exercise.
10. I don’t know where (stay) for the night.
11. He dislikes (live) in the village.
12. I arranged (meet) him in a hotel.
Answer:
1. coming
2. coming
3. to see
4. Believing
5. having come
6. winning
7. doing
8. speaking
9. leave / leaving
10. to see
11. to help
12. expecting.

Punjab State Board PSEB 10th Class Science Important Questions Chapter 14 Sources of Energy Important Questions and Answers.

PSEB 10th Class Science Important Questions Chapter 14 Sources of Energy

Long Answer Type Questions

Question 1.
Draw a labelled diagram of a Box Type Solar Cooker. Also give its working and advantages.
Answer:
Construction: Box type solar cooker consists of an insulated box (wooden or plastic) which is painted black from inside. A plane mirror reflector is attached to the box (figure). The food to be cooked is placed in containers which are also painted black from outside.

A Box Type Solar Cooker

Working: The containers with food to be cooked are placed in the box and the box is covered with thick glass sheet. The cooker is kept in the sunlight and the position of the reflector is adjusted such that a strong beam of sunlight
falls over the glass sheet. These rays pass through the transparent glass sheet cover and are absorbed by the cooker box and the containers and also heat radiations are not allowed to escape. The use of black surface of the box and containers is due to the fact that a black surface absorbs more heat than any other colour. Therefore, the box and the containers absorb maximum amount of infra-red radiations from the sunlight falling on it. As a result, the temperature inside the box rises to about 100°-140°C in two to three hours and this heat cooks the food.

Limitation of Solar Cooker: This type of solar cooker can be used to prepare only food items which require slow heating and cannot be used for baking and frying purposes.

Advantages of a Solar Cooker: The important advantages of a solar cooker are given ahead :

• The use of solar cooker for cooking food materials saves fuel.
• It is an economical method of cooking food since no fuel is used.
• It does not cause any pollution because this does not give out any smoke.
• In this method, food is cooked at comparatively lower temperature therefore, the nutrients of food do not get destroyed during cooking.

Question 2.
With the help of a labelled diagram, describe how electricity is generated in a nuclear power plant?
Answer:
Nuclear Power Plant. It consists the following parts :
1. Nuclear Reactor ‘R’: It is a device in which energy is produced by a controlled nuclear fission of U-235. The reactor R is enclosed in a concrete chamber ‘AT having thick whlls to protect the outside world from nuclear radiations.
The nuclear reaction consists of steel vessel ‘Y having graphite blocks which act as a moderator. The graphite core has number of enriched U-235 rods which act as a fuel. These are marked as ‘A’. In between the uranium rods are inserted cadmium or boron rods and which can be lowered or raised from outside. These rods will keep the fission under control.

2. Heat Exchanger ‘H’: The reactor ‘R’ is connected to a heat exchanger ‘H’ by pipes. The heat exchanger is a sort of bioler which contains water. The heat produced in the reactor is carried to water through coiled pipes.

3. Steam Turbine ‘T’: The heat exchanger is connected to a steam turbine T and its shaft is connected to an electric generator ‘G’. The electricity produced by the generator is sent for transmission.

Working. After the uranium enriched rods are placed in position, the reactor is sealed. The cadmium or boron rods in the beginning are put inside so that they may absorb all neutrons emitted by U-235 and prevent fission all at once. The controlling rods of cadium

Nuclear Power Plant

or boron are withdrawn till they emit desirable number of neutrons. At this stage a controlled reaction takes place. The heat produced is withdrawn by circulating sodium. When sodium passes through the coil in the exchange it transfers heat to water. Now the water changes into steam which is passed into turbine chamber ‘T’. The turbine rotates the coil of the generator ‘G’ when electricity is generated.

Question 3.
Draw diagram of Fixed Dome Type Biogas Plant and describe how biogas can be produced with this plant?
Answer:
Fixed Dome Type Biogas Plant. The plant consists of underground tank made of bricks called digester. The roof of the digester is dome-shaped made of cement and bricks. It acts as a storage tank for biogas. In the mixing tank, cattle dung is mixed with water to prepare slurry. This slurry is then fed into the inlet chamber for onward supply to digester through inlet T. At the bottom of digester and just opposite to the inlet there is outlet ‘O’ taking spent us slurry to the outlet chamber. There is a gas outlet ‘S’ at the top of dome for the supply of bio-gas.

Fixed Dome Type Biogas Plant

Working of Plant: Animal waste and water are mixed in equal proportions in the mixing tank to form a slurry. The slurry is fed into the digester tank through the inlet chamber. The tank is closed for about two months. During this period, the animal waste undergoes fermentation by anaerobic bacteria. As a result of fermentation, biogas is formed and collected in the dome. As more and more biogas gets collected in the dome, it exerts pressure on the slurry in the digestion tank and forces it to go into the over flow tank through the outlet chamber.

The spent slurry being rich in nitrogen and phosphorus can be used as a manure. Whenever required the biogas collected in the dome can be taken out through a pipe ‘S’ Once the biogas plant starts functioning, more and more slurry may be fed into the digester to get a continuous supply of the biogas.

Question 4.
Explain the working of Floating Gas Holder Type Biogas Plant with the help of a neat labelled diagram.
Answer:
Construction of Floating Gas Holder Type Biogas Plant. The plant consists an underground well shaped tank made of bricks. It is called digester. A drum shaped gasholder made of steal meant for collecting gas is kept in the inverted position floating over cattle dung slurry on the digester tank. The up and down movement of gasholder is controlled by a pipe. At the top of the gasholder there is an outlet for gas. The digester tank is divided into two parts with a partition wall. On the left side of the digester tank there is an inlet pipe. The inlet pipe is connected to the mixing tank through which slurry is allowed to get into the digester. On the right side of the digester tank there is an outlet pipe which is connected to the overflow tank.

Floating Gas Holder type Bio-gas Plant

Working: Cattle dung and water are mixed in equal proportions in the mixing tank to make slurry. The slurry is then introduced into the digester tank through the inlet pipe. It is left for about 2 months during which dung undergoes anaerobic fermentation producing biogas. The biogas so produced starts collecting in the gas holder when more and more gas is produced, the gas holder starts rising. The spent up slurry left over is used as manure.

Question 5.
Describe a wind mill and give its functions?
Answer:
Wind mill. A wind-mill is a machine which works with the energy of wind and converts kinetic energy of wind into mechanical energy or electricity. It consists of large fan like blades to catch the wind. When the wind strikes against these blades, the blades start rotating. This motion is then passed onto connected crankshaft and is used to draw water from wells and to run flour mills for grinding grains. The pictures of wind-mill drawing water from tube wells. [Figure] and wind will grinding grains (Figure) are shown ahead.

A wind-mill drawing water from the under ground.

Wind mill used to grind grains.

Functions of Wind Mill.

• Wind mill is used for drawing water from tube wells.
• Wind mill for grinding grains. Windmill is being used to grind grains by suitable arrangement of toothed wheel and shaft.

Question 6.
What is a Solar Cell? What is its working principle? Write short note on the making of solar cells and also give its uses.
Answer:
Solar Cell. It is a device which converts solar energy directly into electricity.

Working Principle. Semi conductors (substances whose conductivity lies between metal and insulator) possess very low electrical conductivity. Silicon (Si), Gallium (Ga) and Germanium (Ge) are some examples of semi-conductors. In fact, semi-conductors are neither conductor nor insulator. However, it has been found that their conductivity increases when they are mixed with phosphorus or arsenic. Since the efficiency of such solar cells made of silicon and gallium was very low (10% to 15%) whereas the efficiency of modern cells is as high as 25%.

Making of Solar Cells. To make a solar cell thin wafers of semi-conducting materials containing impurities are arranged in such a way that when solar light falls on them, a potential difference develops between two areas of the semi-conductor. This potential difference results in producing current. A single solar cell produces an elective current of 60 mA (milli-amperes).

Uses of Solar Cells: The important uses of solar cells are given below :

• It is used for generating electricity for operating on board artificial sattelites and spaceprobes.
• Solar cells are used to provide electricity to “light houses” situated in the sea and off-shore oil drilling platform.
• Solar cells are used for operating electronic watches and calculators.
• Solar cells are used for street lighting, for operating water pumps and working of television in remote areas where electricity is not available.

Question 7.
What is solar cell panel? Describe with the help of a suitable diagram.
Or
How is solar panel prepared? Explain with diagram.
Answer:
Solar Cell Panel: A single solar cell consisting of thin wafer of silicon-arsenic or silicon-boron produces a very weak current. In order to get sufficiently high current so as to be capable of lifting water from deep well or to light a house, a large number of solar cells are joined together in a definite pattern to get solar cell panel.

Solar cell Panel being used for operating a water pump

The above figure depicts a simple arrangement of a solar cell panel. In this solar cell panel hundreds of solar cells are joined together. The electric power produced by this solar cell panel is stored in battery B. This battery runs an electric motor M which drives water pump P to take out water from underground.

Question 8.
What is Nuclear Fission? Explain this phenomenon with the help of an example.
Answer:
Nuclear Fission: The process in which an unstable nucleus of a heavy radioactive atom (like Uranium-235) splits up into two or more fragments of medium weight nuclei when bombarded by slow moving neutrons (possessing low energy) with the release of enormous amount of energy is called Nuclear fission.

In this process there is always a small loss of mass which appears as energy.
Example of Nuclear Fission. When uranium-235 (U-235) atoms are bombarded with slow moving neutrons, the heavy uranium atom breakes up producing two medium weight atoms Barium (Ba) and krypton-94 with the emission of three neutrons and release of a great amount of energy.

The fission reaction can be represented in the form of following nuclear reaction :

In the fission of uranium some mass of uranium is lost which results in the production of large amount of energy. The energy can be made use of for generating electricity.

Question 9.
What is Nuclear Fusion? Explain this phenomenon with the help of an example.
Or
Describe the process by which energy is released by the Sun.
Answer:
Nuclear Fusion: The process in which two nuclei of light atoms (hydrogen atom) combine to form a heavy and more stable atom (helium atom) with the liberation of a large amount of energy is called Nuclear Fusion.

This process is carried out by heating the light atoms to a very high temperature when some loss of mass occurs. This produces a large amount of energy. The energy produced in fusion reaction is much more than in a fission reaction.

Example of Nuclear Fusion. When Deuterium atoms (isotopes of heavy hydrogen atoms of mass number 2) are heated to an extremely high temperature, then two deuterium nuclei combine together to form a heavy nucleus of Helium and enormous energy is released. This nuclear reaction can be represented by the following equation :

• Energy from salinity gradient in seas: The concentration of salts in the waters of different seas is different. The difference in salt concentrations in the water of two different seas is called salinity gradien t. This difference in concentration of salt, where waters from two different seas meet, can be used to obtain energy in usable form.
• Energy from sea vegetation or bio-mass: Sea vegetation or biomass is also an indirect source of energy. For example, the vast sea weed plantation may provide an endless supply of methane fuel in future.
• Energy from the nuclear fusion of deuterium present in oceans: The oceans are also a source of deuterium (heavy hydrogen). Attempts are being made to produce energy by carrying out the controlled nuclear fusion of deuterium.

Question 10.
Write three points to distinguish between nuclear fission and nuclear fusion.
Answer:
Differences between Nuclear Fission and Nuclear Fusion.

Nuclear Fission	Nuclear Fusion
1. In a fission reaction, a heavy nucleus breaks up to form two lighter nuclei.	1. In a fusion reaction two light nuclei combine to form a heavy nucleus.
2. Nuclear fission is a chain reaction.	2. Nuclear fusion is not a chain reaction.
3. Fission reactions are carried out by bombarding the heavy nuclei with neutrons.	3. Fusion reactions are carried out by heating the light atoms to an extremely high temperature.
4. Nuclear fission reactions can be controlled to generate electricity.	4. Nuclear fusion reactions have not been controlled so far.
5. Nuclear fission produces a large amount of energy.	5. The energy produced in a nuclear fusion reaction is much more than that produced during fission.

Short Answer Type Questions

Question 1.
What are fossils?
Answer:
Fossils: The hard parts of animals and plants or their ancient imprints on rocks which are found during excavation of rocks, are called fossils. As for example bones of animals, their skeletons, their foot prints are all fossils. This helps in the study of evolution and growth of organisms.

Question 2.
What are fossil fuels? What will happen if fossil fuels are used up at a fast rate? Give reasons for your answer.
Answer:
Fossil Fuels. These are the energy-rich compounds of carbon which were originally made by the plants with the help of solar energy. Fossil fuels like coal, petroleum and natural gas are formed under the earth over a long period of millions of years. So, if we continue to consume fossil fuels at this rapid rate, then all the fossil fuels will be exhausted one day. But the earth will not recreate fossil fuels so rapidly.

Question 3.
Why is L.P.G. considered an ideal fuel?
Answer:
L.P.G. an Ideal Fuel. Because of the following qualities, L.P.G. is considered as an ideal fuel :

• L.P.G. has high calorific value.
• L.P.G. has low ignition temperature.
• L.P.G. on combustion does not produce toxic gases and as such does not cause pollution.
• L.P.G. has balanced rate of combustion.
• L.P.G. contains much less incombustible substance.
• The combustion of L.P.G. is complete. Therefore, it does not leave behind any residue.

Question 4.
State the advantages of the nuclear fusion reactions over nuclear fission reactions. Also state one disadvantage.
Answer:
Advantages of Nuclear Fusion over Nuclear Fission.

• The amount of energy liberated in a fusion reaction is much more than that in a fission reaction.
• The products of a fusion reaction are not radioactive. They are harmless and hence can be disposed off easily.
• On the other hand, the products and by-products of fission reactions are radioactive and hence harmful. So the problem of their disposal arises.

Disadvantage. It has not been possible to have a controlled fusion reaction so far.

Question 5.
How is hydroelectricity generated at hydroelectric power plant? Give its advantages and disadvantages.
Answer:
The basic principle of hydroelectric power is that the potential energy of the water stored in the dams is converted into kinetic energy by allowing the water to fall

Outline of a hydroelectric power station.

from a height on turbines placed at the bottom of dam. The falling water makes the blades of turbines to rotate which in turn rotates the coil of generator placed in a magnetic field. This results in the production of electricity.

Limitations of Water Energy: The flowing water is not available in plenty everywhere to turn the turbines to produce electricity. Therefore, useful work can be obtained from water energy only at limited places where the flow of water is more.

Advantages and Disadvantages of Generating Hydroelectricity
Advantages:

• The use of water energy does not cause any pollution.
• It is an economical and renewable source of energy which will never get exhausted.

Disadvantages:
It causes a number of environmental problems. These are given below :

• The construction of dams on rivers results into a variety of ecological changes in the downstream area of the river. As a result a vast variety of flora and fauna (plants and animals) are destroyed and many people become homeless.
• The soil in the downstream area may become barren because there were no annual floods to deposit nutrient rich silt on the banks of the river. Therefore, there may be ecological imbalance.
  Therefore, while constructing the high-rise dams to generate hydroelectricity, special care should be taken to study its impact on the environment and social life.

Question 6.
What is biogas? Give any four uses.
Answer:
Biogas: The mixture of Methane (CH₄), Carbon dioxide (CO₂) Hydrogen (H₂), Nitrogen (N₂) and Hydrogen Sulphide (H₂S) obtained by degradation of plants and animals wastes in the presence of water due to anaerobic fermentation is called biogas. Its main constituent is Methane (50% – 70%).

Composition of Biogas

Methane	50% – 70%
Carbon dioxide	30% – 40%
Hydrogen	5% – 10%
Nitrogen	1% – 2%
Hydrogen sulphide	very small quantity

Uses of Biogas:

• It is used as fuel for cooking food.
• It is used as a fuel to run engines.
• It is used for street-lighting.

Question 7.
Biogas is considered to be a boon to the farmers. Give reasons.
Answer:
Biogas is considered as a boon to the farmers because :

• They can produce clean fuel from wastes.
• They use spent up slurry as manure.
• They can generate electricity from biogas.

Question 8.
Give two reasons for using gobar (cow dung) in Biogas plant.
Answer:
Use of Gobar in Biogas Plant. The use of cow dung in biogas plants to prepare biogas is preferred because of the following reasons :

• When cow dung is used in biogas plant, the residue left after taking gas from the plant is still rich in nutrients and is used as manure.
• Biogas burns without producing any smoke, so it is a clean fuel and does not cause pollution.

Question 9.
Write the general principle involved in generating nuclear energy. Name one fuel used in a nuclear reactor.
Answer:

• Nuclear energy is generated by a process called nuclear fission.
• In this process nucleus of a heavy atom is bombarded with slow moving neutrons to split it and release a large amount of energy.
• Nuclear Fuel: Uranium, plutonium, thorium are used as nuclear fuels.

Question 10.
What is natural gas? What are its advantages over other fuels?
Answer:
Natural gas: It is a fossil fuel. It consists mainly of methane and small quantities of ethane and propane. Thus, methane is the principal constituent of natural gas (upto 97%). It occurs deep under the earth either alone or along with oil above of the petroleum deposits.

Question 11.
Which way of using cow-dung as fuel for domestic use is better : use of cow-dung cakes or use of cow-dung in a bio-gas plant? Give three reasons in support of your answer.
Answer:
When cow-dung cakes burn, they produces a lot of smoke, which causes air pollution. However, the use of cow-dung in biogas plant is better because of the following reasons :

• bio-gas burns without smoke.
• bio-gas produces a large amount of heat.
• the residue (slurry) left in the plant is rich in nitrogenous and phosphorus compounds and can be used as a useful manure.

Question 12.
Why burning firewood in traditional chulhas is not considered advantageous?
Answer:
Air pollution produced in atmosphere due to smoke in the absence of chimneys and so this is wastage of fuel as efficiency is low and calorific value is not so good. Carbon mono oxide produced due to partial burning of fuel is very much poisonous.

Question 13.
Expand LPG. What are its uses?
Answer:
LPG (Liquefied Petroleum Gas). The petroleum gas liquefied under pressure is called liquefied petroleum gas (LPG). It consists of mainly butane and small amounts of propane and ethane. This is a domestic gas which we ordinarily use.

Uses of LPG:

• It has a high calorific value.
• It does not produce any poisonous gases on burning.
• It is easy to handle and convenient to use.
• It does not cause pollution.

Question 14.
Explain why :
(a) Solar cookers are covered with glass plate.
Answer:
To attain the high temperature the solar cookers are covered with glass plate. This plate focuses the sun rays to a point and temperature inside the box is increased.

(b) The solar cooker is painted black from inside.
Answer:
The black surface of the solar cooker absorbs more heat as compared to white surface.

Question 15.
Write any two limitations of solar heating devices.
Answer:
Limitations of Solar Heating Devices:

• It saves fuel.
• The nutrients of food do not get destroyed during cooking.
• If does not produce pollution.
• Its maintenance cost is low.
• It is easy to handle and there is no danger of any mishap.

Question 16.
Why is it not possible to make use of solar cells to meet all our energy needs? State at least three reasons to support your answer.
Answer:
Solar cells do not meet all our energy needs due to :

• High cost of installation.
• Limited availability of special grade silicon to make solar cells.
• Unavailability of efficient system to store electrical energy generated by solar panels.

Question 17.
Write four areas where solar cell is used as source of energy?
Answer:
Uses of Solar Cells:

• It is used for generating electricity for operating on board artificial sattelites and spaceprobes.
• Solar cells are used to provide electricity to “light houses” situated in the sea and off shore oil drilling platform.
• Solar cells are used for operating electronic watches and calculators.
• Solar cells are used for street lighting, for operating water pumps and working of television in remote areas where electricity is not available.

Question 18.
Hydrogen gas has high calorific value but it is not used as a domestic fuel. Why?
Answer:
Though hydrogen has very high calorific value, yet it is not used as a domestic fuel because of the following reasons :

• It is highly combustible gas and its combustion cannot be controlled.
• Its transportation is difficult.
• Its cost of production is high.

Question 19.
What is sind mill? Write its two advantages.
Answer:
Windmill: A wind-mill is a machine which works with the energy of wind and converts kinetic energy of wind into mechanical energy or electricity. It consists of large fan like blades to catch the wind. When the wind strikes against these blades, the blades start rotating. This motion can then be passed on to connected crankshaft and is used to draw water from wells and to run flour mills for grinding grains.

Advantages of Wind Mill.

• Wind mill is used for drawing water from tube wells.
• Wind Mill for Grinding Grains. Wind mill is used to grind grains by suitable arrangement of toothed wheel and shaft.

Question 20.
On what basis would you classify energy sources as :
(а) renewable and non-renewable?
(b) exhaustible and inexhaustible?
Are the options given in (a) and (6) same?
Answer:

• Sources of energy that will get depleted some day are said to be exhaustible sources or non-renewable sources of energy.
• Sources from which we can be assured of constant supply of energy at a particular rate i.e., the sources which can be regenerated are called renewable sources of energy.
• Inexhaustive or renewable energy is one for which the depletion of the reservoir because of extraction of useable energy is practically negligible.
• We are getting energy from sun for last five billion years and we go on getting it for another five billion years, therefore we can say solar enegy is inexhaustible or renewable.
• Coal reserve with us are for about 200 years whereas it will take millions year for it to form again, hence coal may be said to be exhaustible or non-renewable source of energy.
• Thus inexhaustible is renewable and exhaustible is non-renewable.

Question 21.
What are fossil fuels? How are they formed? Why are they non¬renewable sources of energy?
Answer:
Fossil fuels. Fossil fuels are the energy rich compounds of carbon which are formed in many-many years from the remains of dead plants and animals in the absence of oxygen under the combined effect of pressure, temperature and bacteria.

Examples. Coal, petroleum and natural gas.
Formation of Fossil fuels. The plants and animals which died millions of years ago got buried deep under the earth away from reach of oxygen. The cover of sediments prevented their oxidation and they got squeezed due to the weight of sediments and got converted into water and volatile materials. Thus in the absence of oxygen and under the combined effect of high pressure, high temperature and bacteria. The remains of plants and animals were converted into fossil fuels. The fossils of smaller plants and animals got converted into oil and gas while the fossils of large plants got converted into coal.

Fossil fuel is non-renewable source of energy since it takes millions of years to form these fuels. It should be used only when it is needed.

Question 22.
What is greenhouse effect? Explain in detail.
Answer:
Greenhouse Effect. Carbon dioxide content of the air is increasing due to deforestation and combustion in industries, automobiles and planes, and is likely to become double by 2020. This increase is affecting the atmospheric composition and balance of gases, which are among the factors that control earth’s climate. Increase of carbon dioxide causes rise in atmospheric temperature, producing what is called the Greenhouse Effect. A rise of global temperature by more than 2 or 3 degrees may melt glaciers and polar ice. This will cause rise in ocean level and consequent flooding of coastal towns and submersible of islands. Rainfall pattern may also change, affecting agricultural output.

Question 23.
Differentiate between renewable and non-renewable sources of energy.
Answer:
Non-renewable sources of energy. Wood, fossil fuels like coal petroleum, natural gas, alcohol etc; Also called conventional sources of energy. Fossil fuels if consumed at the present speed are not going to last beyond 2050 AD. It takes millions of years to form fossil fuel. Such sources which cannot be formed again are called non-renewable sources of energy. Consumption of non-renewable sources cause high concentration of harmful gases. This has also led to depletion of ozone layer and global warming. Pollution caused by vehicles cause huge health hazards.

Renewable sources of energy. These sources are called non-conventional or renewable sources of energy. The sun, hydel (water) and wind energies can never get exhausted. All the renewable sources of energy are non-polluting and absolutely safe.

Geothermal energy derived from hot rocks, magma and hot water natural geyser, ocean thermal energy derived from waves and tidal waves are absolutely safe. Fuel cells use hydrogen and oxygen to produce electricity. Nuclear energy is the other source of non-conventional energy but it is very hazardous to harness.

Question 24.
“Oceans are vast store of energy”. Justify this statement.
Or
What is ocean thermal energy (OTE)?
Answer:
Oceans and seas are sources of large amount of energy. The following are factors responsible for energy production.

• Kinetic energy of sea waves can produce electricity.
• Tides and ebbs caused by moon and sun attraction can rotate turbines to produce electricity.
• Sea vegetation can be used as fuel.

Question 25.
What are solar reflectors and solar concentrators?
Answer:
Solar Reflectors. Those devices in which the sun rays are reflected by plane mirrors and let rays fall on containers which are black in colour. These containers absorb rays due to their black surface and get heated up, are called solar reflectors.

Solar Concentrators. When high temperature is needed, the sun rays are concentrated by parabolic mirror or converging lens at a point.

Main Components of a Solar cooker

• Blackened surface.
• Ordinary glass sheet.
• Suitable arrangement of mirrors.
• Insulated box.

Very Short Answer Type Questions

Question 1.
What are constituents of coal gas?
Answer:
It is a mixture of 55% hydrogen, 30% of methane, 10% of carbon monoxide and 5% of ethylene.

Question 2.
Write two examples of fossil fuels.
Answer:
Fossil fuels are those which are present inside earth’s crust as remains of animals and plants. Coal, petroleum, natural gas etc., form fossil fuels.

Question 3.
What is the range of temperature which can be attained in a box type solar cooker in two to three hours exposure to sun?
Answer:
100°C to 140°C.

Question 4.
Name the device which directly converts solar energy into electrical energy.
Answer:
Solar cell.

Question 5.
What is biogas?
Answer:
Biogas. It is a mixture of gases such as methane, carbon dioxide, hydrogen and hydrogen sulphide produced by the decay of biomass in the absence of air.

Question 6.
Name the main constituent of biogas.
Answer:
The main constituent of biogas is methane.

Question 7.
Name two main components of biogas.
Answer:
Methane (CH₄) and hydrogen.

Question 8.
List two nutrients in which the slurry left behind in the digester is rich?
Answer:
It is rich in nitrogenous and phosphorus compounds.

Question 9.
What type of energy is possessed by huge waves near the seashore?
Answer:
Kinetic energy.

Question 10.
What is tidal energy?
Answer:
The energy possessed by the rising and falling water in tides.

Question 11.
Define energy.
Answer:
Energy. The ability to do work is energy.

Question 12.
Define kinetic energy.
Answer:
Kinetic energy. The energy possessed by a body due to its motion is called kinetic energy.

Question 13.
Name three fossil fuels.
Answer:
Coal, Petroleum and Natural gas.

Question 14.
Define Solar Energy.
Answer:
Solar Energy. The energy produced by sun is called solar energy.

Question 15.
What is calorific value of a fuel?
Answer:
Calorific value. The heat produced by full burning of unit mass of fuel is called calorific value of the fuel.

Question 16.
From which substances is biogas obtained?
Answer:
It is obtained from plants and animals waste, cattle dung, domestic waste, wastes from poultry.

Question 17.
Name the constituents of Biogas.
Answer:
CH₄, CO₂ and H₂S. The percentage of methane is 65%.

Question 18.
Name any two materials used for making of solar cells.
Answer:
Selenium, gallium, silicon etc.

Question 19.
Define wind energy.
Answer:
Wind energy. The energy possessed by moving air (wind) is called wind energy. Wind possesses kinetic energy due to its motion.

Question 20.
What is biomass? Write its uses.
Answer:
Biomass is the decomposed mass of animals and plants. It is the total matter present in the bodies of plants and animals.

Uses:

• It is used as a biofuel.
• These give energy by burning.

Question 21.
Which type of mirror is most suitable in the device shown in figure below?

Answer:
Plane Mirror.

Question 22.
Name the device shown in the given diagram. What is being prepared in it?

Answer:
The device shown in the figure is Fixed Dome type Biogas Plant. In this plant Biogas is being Prepared.

Question 23.
Label 1 and 2 in the given figure.

Answer:
1 – Plane mirror
2 – Wooden Box

Multiple Choice Questions

Question 1.
Non-renewable source ________
(A) Solar energy
(B) Wind energy
(C) Natural gas
(D) Water.
Answer:
(C) Natural gas

Question 2.
________ is used in Hydro-electric power station.
(A) Wind energy
(B) Energy of running water
(C) Energy produced from burning coal
(D) All of these.
Answer:
(B) Energy of running water

Question 3.
________ is used in thermal power station.
(A) Wind energy
(B) Energy of flowing water
(C) Energy produced from burning fossil fuel
(D) All of these.
Answer:
(C) Energy produced from burning fossil fuel

Question 4.
The temperature range of Box Type solar cooker kept in the sun for 2-3 hours will be ________
(A) 60° C – 80° C
(B) 80° C – 100° C
(C) 100° C – 140° C
(D) 140° – 180° C.
Answer:
(C) 100° C – 140° C

Question 5.
________ converts solar energy into electric energy
(A) Solar water heater
(B) Solar cell panel
(C) Solar furnace
(D) Solar cooker.
Answer:
(B) Solar cell panel

Question 6.
________ is used in making solar cell
(A) Carbon
(B) Silicon
(C) Sodium
(D) Cobalt.
Answer:
(B) Silicon

Question 7.
The device that converting energy into mechanical energy is called ________
(A) Solar cooker
(B) Solar cell
(C) Engine
(D) All the above.
Answer:
(C) Engine

Question 8.
Which of the following is not a source of Bio-mass energy?
(A) Wood
(B) Gobar gas
(C) Coal
(D) Nuclear energy.
Answer:
(D) Nuclear energy.

Question 9.
Which one of the following is not a solid fuel?
(A) Coal
(B) Wood
(C) Coke
(D) Kerosene.
Answer:
(D) Kerosene

Question 10.
Which one is a non-renewable / source of energy?
(A) Wind
(B) Sun
(C) Fossil fuel
(D) Water.
Answer:
(C) Fossil fuel

Question 11.
The main source of energy is ________
(A) Sun
(B) Water
(C) Uranium
(D) Fossil fuel.
Answer:
(A) Sun

Question 12.
Slurry obtained from Biogas Plant contains maximum quantity of ________
(A) Sulphur, Phosphorus
(B) Carbon, Sodium
(C) Nitrogen, Oxygen
(D) Phosphorus, Nitrogen.
Answer:
(D) Phosphorus, Nitrogen

Question 13.
Which country is called the country of Winds?
(A) India
(B) Italy
(C) France
(D) Denmark.
Answer:
(D) Denmark

Question 14.
The combination of solar cells is called ________
(A) Solar Panel
(B) Solar Band
(C) Solar Circle
(D) Solar Plate.
Answer:
(A) Solar Panel

Question 15.
The element used in manu¬facturing solar cells is ________
(A) Copper
(B) Tungsten
(C) Sulphur
(D) Silicon.
Answer:
(D) Silicon

Question 16.
The vast source of energy on the earth is ________
(A) Wood
(B) Coal
(C) Sun
(D) Moon.
Answer:
(C) Sun

Question 17.
Natural gas is mostly :
(A) Methane
(B) Ethane
(C) Propane
(D) Pentane.
Answer:
(D) Pentane.

Question 18.
Solar water heater cannot be used to get hot water on :
(A) Sunny day
(B) Cloudy day
(C) Hot day
(D) Windy day.
Answer:
(A) Sunny day.

Question 19.
Which one of the following energies are freely available?
(A) Bio gas
(B) Sunlight
(C) Water gas
(D) Hydrogen.
Answer:
(B) Sunlight.

Question 20.
Which of the following is needed for formation of biogas from cow dung?
(A) Water
(B) Oxygen
(C) Carbon dioxide
(D) Hydrogen.
Answer:
(B) Oxygen

Fill in the blanks:

Question 1.
Non-renewable sources of energy must be used ________ as possible.
Answer:
rarely.

Question 2.
Sun produces huge amount of energy due to nuclear ________
Answer:
fusion.

Question 3.
The slurry left behind in a biogas plant is a good ________
Answer:
manure.

Question 4.
The fuels obtained from under the earth are called ________ fuels.
Answer:
fossil.

Question 5.
A black surface absorbs ________ heat as compared to white surface.
Answer:
more.

Punjab State Board PSEB 10th Class Science Book Solutions Chapter 14 Sources of Energy Textbook Exercise Questions and Answers.

PSEB Solutions for Class 10 Science Chapter 14 Sources of Energy

PSEB 10th Class Science Guide Sources of Energy Textbook Questions and Answers

Question 1.
A solar water heater cannot be used to get hot water on a :
(a) sunny day
(b) cloudy day
(c) hot day
(d) windy day.
Answer:
(b) cloudy day.

Question 2.
Which of the following is not an example of a bio-mass energy source?
(a) wood
(b) gobar gas
(c) atomic energy
(d) coal.
Answer:
(c) atomic energy.

Question 3.
Most of the sources of energy we use represent stored solar energy. Which of the following is not ultimately derived from the Sun’s energy?
(a) geothermal energy
(b) wind energy
(c) nuclear energy
(d) bio-mass.
Answer:
(c) nuclear energy.

Question 4.
Compare and contrast fossil fuels and the sun as sources of energy.
Answer:
Similarities.

• Both are natural sources of energy.
• Both are widely used sources of energy.
• No technology is required to get energy by any of these sources.

Dissimilarities/Contrast.

• Sun’s energy can be used only during day time but fossil fuel can be used to get energy at any time during day or during night.
• Solar energy is almost free whereas fossil energy costs much.
• Infinite amount of solar energy is available almost free of cost whereas there is a limited reserve of fossil fuel.
• Solar energy is a renewable source of energy whereas it takes millions of year to produce fossil fuel.
• Solar energy is totally pollution free whereas fossil fuel causes a lot of pollution on burning.

Question 5.
Compare and contrast bio-mass and hydroeiectricity as a source of energy.
Answer:
Similarities.

• Both bio-mass and hvdro-electricity are natural sources of energy.
• Working cost of both the sources of energy as low. However, initial installation cost of hydro-electricity sources is higher than bio-mass source.
• Both are widely used sources of energy.
• Hydroelectric plants can be erected only at specific points while biomass plant can be installed anywhere.
• The energy produced by hydro-electric plant is much more than produced by biomass plant.

Dissimilarities.

Biomass	Hydroelectricity
1. Biomass is a renewable and conventional source of energy.	1. Hydroelectricity is also a renewable and conventional source of energy.
2. itse of biomass energy causes pollution of air.	2. Hydroelectricity does not cause any pollution of air.
3. Biomass possesses chemical energy.	3. Hydroelectricity possesses kinetic energy.
4. It does not cause ecological imbalance.	4. Construction of hydroelectric plant causes ecological imbalance.
5. It is economical source of energy.	5. It is relatively costly source of energy.

Question 6.
What are the limitations of extracting energy from :
(a) the wind
Answer:
Limitations of Wind Energy.

• It is not available at all times and at all places since it depends upon the availability of wind.
• The minimum wind speed required to run windmills should be 15 km h_1.
• The initial cost of construction of windmill farm is very high.

(b) waves
Answer:
Limitations of wave energy.

• The wave is not available at all times for generating electricity.
• The power from wave energy is expensive because the plant required to be set up for trapping energy from waves is very costly.
• The output power obtained from waves is not constant.

(c) tides
Answer:
Limitations of tidal energy.

• There are a few locations for constructing dams for harnessing tidal energy.
• The power generation by harnessing tidal waves is very high because the cost of construction of dams for this purpose is very costly.

Question 7.
On what basis would you classify energy sources as :
(a) renewable and non-renewable.
(b) exhaustible and inexhaustible.
Are the options in (a) and (b) same?
Answer:
(a) Renewable Sources of Energy. Those sources of energy which after depletion (used up) can be replenished (brought back to its original form) are called renewable sources of energy, e.g., water, wind, tides and ocean.
Those sources of energy which can not be replenished (regenerated) after when these are used up are called non-renewable sources of energy, e.g., fossil fuels, coal and petroleum.

(b) Exhaustible Sources of Energy. Those sources of energy which will get depleted some day are called exhaustible sources of energy. Exhaustible sources are non-renewable sources of energy.

Inexhaustible Sources of Energy. Those sources of energy which get replenished even after extraction of usable energy and are never depleted are called inexhaustible sources of energy. Inexhaustible sources of energy are renewable sources of energy.

Question 8.
What are characteristics of an ideal source of energy?
Answer:
Characteristics of an ideal source of energy. An ideal source of energy should have the following qualities :

• It should give adequate amount of energy at steady rate.
• It should be safe and convenient to use.
• It should do large amount of work per unit volume or mass.
• It should be economical.
• It should be easy to store and transport.

Question 9.
What are the advantages and disadvantages of using a solar cooker? Are there places where solar cookers have limited utility?
Answer:
Advantages of using Solar Cooker.

• It saves fuel.
• The nutrients of food do not get destroyed during cooking.
• If does not produce pollution.
• Its maintenance cost is low.
• It is easy to handle and there is no danger of any mishap.

Disadvantages of using Solar Cooker

• Solar energy is not available in ample amount and uniformly all the time and at all places. It cannot be used at night and on cloudy days.
• Direction of reflector of solar cooker has to be changed continuously towards the direction of sun rays.
• It can not be used for cooking chapatis or for frying purpose.
• It takes more time to cook food.

Yes, there are places where solar cookers have limited utility. At poles solar cooker has limited utility because here sun remains absent for six months. In hilly areas also the sun has limited utility because the sun shines for limited time and where inclined sun rays reach, the use of solar cooker becomes difficult.

Question 10.
What are environmental consequences of the increasing demand for energy? What steps would you suggest to reduce energy consumption?
Answer:
The demand of energy is increasing day by day. Exploiting any source of energy may disturb the environment in one way or the other. For example, getting energy from fossil fuel may cause air pollution and getting energy by nuclear fission may create problem of disposal of nuclear waste.

Steps for reducing energy consumption should be such that we get maximum energy from least fuel.
For this :

• Under the given situation the best possible technology should be utilised. For example, smokeless chullahs should be preferred to traditional chullahs.
• Energy should he extracted by most economic method under the given situation. Whereas energy extraction by solar cell may be useless in big towns due to cost factor, it may be indispensable for artificial satellites.
• Energy saved is energy produced. Therefore, wastage of energy should be strictly avoided.
• Sources of energy should be such that it causes least damage to environment.

Science Guide for Class 10 PSEB Sources of Energy InText Questions and Answers

Question 1.
What is a good source of energy?
Or
Write characteristics of an ideal source of energy.
Answer:
Characteristics of a good source of energy are :

• It should be sustainable and renewable source of energy.
• It should provide great amount of energy per unit mass or volume.
• It should be easily accessible and provide energy for a longer period of time.
• It should not cause pollution.
• It should be economic to use.
• It should be safe for the surrounding individuals.

Question 2.
What is a good fuel?
Or
What are the characteristics of an Ideal fuel?
Or
Give three characterisitcs of a good fuel.
Or
Give the properties of an ideal fuel.
Answer:
Characteristics of a Good Fuel. A good fuel is that which :

• Has high calorific value when burnt it should produce large amount of heat per unit mass.
• Should produce less smoke or preferably no smoke and should not leave any residue (ash).
• Should be economical (low cost).
• Should produce no pollution.
• Should have steady rate of combustion.
• Should be easy to store and produce no hazard to transport and easy to handle.

Question 3.
If you could use any source of energy for heating your food, which one would you use and why?
Answer:
For heating my food I would use fuel which fulfills the most of the characteristics of a good fuel such as

• high calorific value
• pollution free
• easily available
• cheap.

For this I would use L.P.G. if living in a city and wood/gobar gas if living in a remote village.

Question 4.
What are the disadvantages of fossil fuels?
Answer:
Disadvantages of fossil fuels (Non-renewable fuels) :

• Burning of fossil fuels such like petrol, diesel, coal, natural gas etc. causes air pollution.
• Burning of fossil fuels produces carbon dioxide (CO2), a green house gas which causes global warming.
• On burning fossil fuels, oxides of carbon, nitrogen and sulphur are released. This leads to acid rain which affects our soil and water resources.
• There are limited resources of fossil fuels since these were formed over millions of years and their continuous use would exhaust them and make them unavailable after some time.

Question 5.
Why are we looking at alternative sources of energy?
Answer:
With the development of technology and swelled up population, the demand for energy has increased manifold which cannot be met with traditional non-renewable sources. We are, therefore, looking for alternative sources of energy because :

• Fossil fuels like coal and petroleum which are traditional sources of energy are non-renewable and are not going to last long.
• The traditional sources of energy are costly and cause pollution whereas alternative sources of energy like solar energy, wind energy and water energy do not cause pollution and are almost free of cost except for their installation cost.

Question 6.
How has the traditional use of wind and water energy been modified for our convenience?
Answer:
Traditional use of wind energy was made to lift water from the well and run grinding machine to grind grams. The traditional use of wind energy has now been modified to generate electicity where turbines are made to rotate by the use of wind energy.

Likewise, the traditional use of water energy has been modified to generate electricity in hydropower plants. Water is collected in dams. It is then made to fall on turbines where potential energy of collected water is transformed into kinetic energy of running water which is made use of in running turbines and thus converting into electricity.

Question 7.
What kind of mirror-concave, convex or plane would be best suited for use in a solar cooker? Why?
Answer:
A concave mirror is the best for use in solar cooker for it focuses sun rays from large areas to a specific point. These concentrated heat rays produce large amount of heat at that point.

Question 8.
What are the limitations of the energy that can be obtained from the oceans?
Answer:
The energy obtained from oceans can be of the following kinds :
1. Tidal Energy. Due to attraction of the moon, there are high and low tides in the sea. Tidal energy is harnessed by constructing dam across a narrow opening in the sea and a turbine fixed at this opening converts tidal energy of waves into electricity.

The limitation of this kind of energy is there are only a few such locations available where dams can be constructed for production of energy. Therefore, this kind of energy will not be enough for commercial use.

2. Ocean Thermal Energy (O.T.E.) Due to sunlight, water at the surface of the ocean gets heated up while water in the deeper regions is relatively cold. This difference in temperature is exploited to get electric energy which is called ocean thermal energy. But the limitation of conversion efficiency is very low. These plants for generating electricity is that these plants work only when the temperature difference of water at the surface and at the depth upto 2 km is 20° C or more. Secondly, its operational cost is high and the efficiency is very low.

Question 9.
What is Geothermal energy?
Answer:
Geothermal energy. Due to changes taking place within earth, molten rocks formed in the deeper hot regions of earth are pushed upward in the regions called ‘hot spots’. Steam is generated when underground water comes in contact with hot spots. The energy which is directly obtained from the heat inside the earth is called geothermal energy. Steam trapped in is passed through a pipe to the turbine can generate electricity.

Question 10.
What are the advantages of nuclear energy?
Answer:
Advantages of Nuclear Energy.

• A smaller space is required to get nuclear energy.
• Nuclear energy is a non-conventional source of energy and produces large quantity of usable form of energy.
• It costs less.
• It is almost pollution free energy.

Question 11.
Can any source of energy be pollution free? Why or why not?
Or
Name two energy sources that you consider pollution free. Give reasons.
Answer:
No source of energy can be perfectly pollution free e.g., bio-mass energy, hydro energy, wind energy, geothermal energy, solar energy is almost pollution free but the process involved in making these plants might have damaged the environment in some way.

Question 12.
Hydrogen has been used as a rocket fuel. Would you consider it a cleaner fuel than C.N.G.? Why or why not?
Answer:
Hydrogen is a cleaner fuel than C.N.G. because the burning of hydrogen produes water which does not pollute the atmosphere. On the other hand, C.N.G. when burnt produces carbon dioxide and water. This carbon dioxide does produce greenhouse effect which ultimately leads to heating of environment. Hence, hydrogen is positively a cleaner fuel than C.N.G.

Question 13.
Name two energy sources that you would consider to be renewable. Give reasons for your choice.
Answer:
Two renewable sources of energy are :
1. Hydro energy. It is the energy generated by using kinetic energy of running water to run dynamo. Hydro power is the main source of electricity now a days. Down from high altitude is utilized to trap energy for generating electricity and the unused water utlimately goes to oceans.

Due to cyclic process (water → water vapour → clouds → rain→snow→running water at dams) again we get water. Water stored in reservoirs at dams is used for generating electricity. So hydro energy is a renewable source of energy.

2. Wind Energy: Wind energy is the kinetic energy due to motion of large mass of air. Wind energy can be used to sail boats, run windmills to produce electric power. Sun rays near the equator are stronger than in the polar region. As a result, air in the equitorial region becomes hot and rises up while cooler air in the polar region moves towards the equator. This causes the flow of air (wind). This process goes on in nature due to temperature differences, so wind energy is a renewable form of energy.

Question 14.
Give the names of two energy sources that you would consider to be exhaustible. Give reasons for your choice.
Answer:
Coal and petroleum are two energy sources which are exhaustible. It takes millions of years for the formation of petrol and coal inside the earth. Its reserves are limited. Coal if used at the present rate will not last beyond two hundred years whereas petroleum products which are being used extensively are expected not to last more than 50 years. Therefore, these energy sources are exhaustible in nature.

Punjab State Board PSEB 10th Class English Book Solutions English Grammar Modals Exercise Questions and Answers, Notes.

PSEB 10th Class English Grammar Modals

Fill in the blanks with suitable Modals :

Question 1.
1. ……. I see my wife now, doctor ? (Can/Could) (not very sure)
2. ………….. I smoke here? (May/Might)
3. He ………….. help you if you ask him. (will/shall)
4. Rahul …………… drive a car even at the age of twelve. (can/could)
5. This …………… be a Satyajit Ray film. (may/might) (not very sure)
6. He ……………. be hiding. (can/may) (doubt but rather sure)
7. Ram …………… come today. (can/might/may) (very uncertain).
8. …………… I take leave of you ? (Can/May) (asking permission)
9. It ……………. rain today. (can/may) (greater possibility)
10. As he tried his best, he ………….. easily win the game. (can/could)
Answer:
1 Could
2. May
3. will
4. Could
5. might
6. can
7. might
8. May
9. can
10. Could

Question 2.
1. You ………….. complete your homework now. (should/must) (compulsion)
2. You ………… be home by 11 o’clock. (should/must) (order)
3. Rita ………….. speak English fluently. (can/would) (showing ability)
4. He told me that he ……………. return to his native land soon. (will/would)
5. Mohan ………….. still be lying in bed. (will/must) (habitual prediction)
6. That ………….. be the postman. (will/must) (prediction)
7. I ………….. smell a fire burning. (can/will) (showing ability)
8. Diana …………… have suffered badly after the car crash. (must/shall) (supposition)
9. I …………. like to have a cup of coffee. (will/would) (wish)
10. ……………. that I were rich ! (Will/Would) (a wish)
Answer:
1. must
2. must
3. can
4. would
5. must
6. must
7. can
8. must
9. would
10. would

Question 3.
1. Duty …………… be done. (should/must) (greater determination)
2. I wish he ……………. stand first. (will/would) (to express a wish)
3. We ………….. respect our elders. (should/must) (to express duty in a more determined sense)
4. How ………….. you talk to me like this ? (need/dare)
5. How ……………. you do it ! (dare/need) (challenge)
6. Your headache ………….. also be due to some other problem. (can/could) (not very sure)
7. I am sure it ………… be cured. (can/may) (very sure)
8. It ……………. be Jaya. (can/may) (not very sure)
9. I ……………. go to the bazaar today. (may/can) (not very sure)
10. Ram …………… take exercise daily. (must/should) (less determination)
Answer:
1. must
2. would
3. must
4. dare
5. dare
6. could
7. can
8. may
9. may
10. should

Question 4.
1. We …………. serve our country. (ought to/ should) (not so forceful)
2. You ………….. not waste your time. (should/must) (more forceful)
3. If wishes were horses, beggars …………….. ride. (will/would)
4. …………… I take her out, mother? (Can/Could) (more polite)
5. ……………. I come in, sir ? (May/Can) (more formal)
6. It …………. rain today. (may/might) (less uncertain)
7. The sun …………. rise in the east. (will/shall) (to express general facts)
8. Had you worked hard, you …………… have passed. (would/should)
9. I …………. rather die than beg. (will/would) (to express a preference)
10. Walk fast lest you …………… miss the train. (shall/should)
Answer:
1. ought to
2. must
3. would
4. Could
5. May
6. May
7. will
8. would
9. would
10. should

Question 5.
1. I told him that he …………… take the test. (can/could)
2. You ………….. leave now. (may/might) (permission in a less formal manner)
3. The teacher ………….. be busy at this time. (can/must) (to express a greater possibility)
4. She told me that he ………….. go. (will/would)
5. I …………… teach him a lesson. (will/would) (to express a threat)
6. She …………… marry Sham. (will/must) (insistence)
7. You …………… attend the evening class. (must/will) (greater compulsion)
8. …………… you give me a glass of water, please ? (Can/Could) (request in a more formal manner)
9. You …………. reach there in time. (must/should) (order in a more determined sense)
10. ………… I answer your question ? (Should/Need) (requirement)
Answer:
1. could
2. may
3. must
4. would
5. will
6. must
7. must
8. should
9. must
10. Need

Question 6.
1. It ………….. be true. (may/might) (very unsure)
2. I wish I ……………. help you, but I have my own problems. (can/could)
3. ….. that I were a king ! (Will/Would)
4. If I were the Prime Minister, I ………….. fight corruption. (will/would)
5. Had I reached the station in time, I ……………. have caught the train. (will/would)
6. This is a film you …………… not avoid. (must/can) (insistence)
7. I ………….. dance Bharatanatyam. (can/may) (ability)
8. You …………. not leave without my permission. (will/shall) (threat)
9. He was so weak that he ………….. not walk. (could/would)
10. I told him that he ………….. leave. (can/could)
Answer:
1. might
2. Could
3. Would
4. Would
5. Would
6. must
7. can
8. shall
9. could
10. could

Question 7.
1. He …………. like to spend an evening with you. (will/would)
2. The headmaster …………… check all these accounts. (should/dare)
3. ……………. you like to take coffee ? (Can/Would)
4. If you meet him, you ………….. tell him about it. (might/must)
5. He …………… be rich, but he is very cruel. (will/may)
6. We ……………. show respect to our elders. (ought to/can)
7. The doctor told me that I …………… not smoke any more. (must/will)
8. …………… you possibly lend me a thousand rupees ? (Could/Will)
9. You …………… not enter my class, I forbid it. (must/will)
10. We ………….. keep our neighbours as happy as we can. (may/should)
Answer:
1. Would
2. should
3. Would
4. must
5. may
6. ought to
7. must
8. could
9. must
10. should

Question 8.
1. I …………… help him with money before I leave for London. (will/would)
2. The children asked if they ………….. have ice cream. (can/could)
3. We ………….. do as we are told. (can/should)
4. Work hard lest you …………… fail. (may/should)
5. You …………. respect your elders. (ought to/can)
6. ……………. I come in ? I am sorry to be late. (May/Shall)
7. He has been absent for a fortnight, he …………. be ill. (must/will)
8. You …………. not see him, just write a letter. (need/dare)
9. We ………….. go to the station by taxi, it is getting late. (may/should)
10. I ……………. not come yesterday since I was too busy. (would/could)
Answer:
1. will
2. could
3. should
4. should
5. ought
6. May
7. must
8. need
9. should
10. could

Question 9.
1. You …………… clean your teeth every morning. (shall/should)
2. It ………….. rain today. (may/might) (very little possibility)
3. This box is very heavy; I ……………. lift it. (can’t/may not)
4. You ………….. take a taxi or you will miss the train. (shall/should)
5. …………… you like to read this book ? (Will/Would)
6. ………. you lift this elephant ? (Can/Will)
7. It is getting late; we …………… go home. (should/can)
8. I ………….. run five miles in an hour.(can/shall)
9. You ………….. go out for a walk every day. (must/may)
10. Why didn’t you inform me ? I ……………. have lent you the money. (can/could)
Answer:
1. should
2. might
3. can’t
4. should
5. Would
6. Can
7. should
8. can
9. must
10. could

Question 10.
1. …………… you finish your work in two hours ? (Can/May)
2. …………… his soul rest in peace ! (May/Might)
3. The doctor says that I ……………. eat anything I like. (can/may)
4. Walk carefully lest you ……………. sprain your foot. (may/should)
5. You ………….. not take this trouble. I’ll do that. (need/may)
6. The door of his room is not locked, he …………… be in. (may/shall)
7. Forty years ago, only the rich …………… think of owning – a radio set. (can/could)
8. ………… you like to get rid of that troublesome fellow ? (Would/Can)
9. You …………… not hurry; there is plenty of time. (need/may)
10. You …………. have returned these books last week. (should/shall)
Answer:
1. Can
2. May
3. can
4. should
5. need
6. may
7. could
8. Would
9. need
10. should

Auxiliary Verb

(सहायक क्रिया)-जिस Verb का अपना कोई महत्त्व न हो, किन्तु वह मुख्य Verb के साथ मिल कर Tense के बनाने में सहायता करे, उसे Auxiliary Verb अथवा Helping Verb कहा जाता है; जैसे

1. She is going home.
2. I have finished my work.
3. You will win a prize.
4. I can solve this question.
5. He was playing cricket.

Types Of Auxiliaries

सहायक क्रियाएं दो प्रकार की हो सकती हैं
1. Primary Auxiliaries : Be : am, is, are, was, were, do, does, did, have, has,had.
2. Modal Auxiliaries : Will, would, shall, should, can, could, may, might, must (am to, is to, are to, have to, etc.) ought to, used to, need, dare.

The Use Of Some Modals

Will and Shall का प्रयोग Will और Shall सम्बन्धी प्रयोग के लिए निम्नलिखित नियम ध्यान में रखिए
In Assertive Sentences

(1) यदि किसी भविष्य की घटना का केवल साधारण रूप में ही वर्णन करना हो, तो
First Person के लिए shall का प्रयोग किया जाता है। Second और Third Persons के लिए will का प्रयोग किया जाता है।
1. I shall finish my work quickly.
2. He will finish his work quickly.
3. We shall not be able to come.
4. They will not be able to come.

(2) यदि वाक्य में किसी भविष्य सम्बन्धी आदेश (command), प्रण (promise), निश्चय (determination),
धमकी (threat), आदि का वर्णन हो तो
First Person के लिए will का प्रयोग किया जाता है।
Second और Third Person के लिए shall का प्रयोग किया जाता है।
1. I will return your money without fail.
2. We will not withdraw from the contest.
3. You shall be punished for your misconduct.
4. You shall not live in my house any longer.

Would तथा Should का प्रयोग

(1) Would का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. Will का Past.
1. I told him that I would come.
2. The doctor knew that the patient would die.

2. प्रार्थना वाचक
1. Would you close the window ?
2. Would you tell me the time ?

3. शर्त वाचक
1. He would pass if he worked hard.
2. He would have passed if he had worked hard.

(2) Should का प्रयोग निम्नलिखित स्थितियों में किया जाता है-

1. उपदेश वाचक — You should give up smoking.
2. सम्भावना वाचक — They should be here by now.
3. नैतिक फर्ज — You should do your duty.
4. Shall at Past — He told me that I should / would pass.

Can तथा Could का प्रयोग

(1) Can का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. योग्यता सूचक — She can dance very well.
2. इजाज़त सूचक — You can go home now.
3. सम्भावना सूचक — It can happen to anyone.
4. Pr. Cont. की जगह — I can hear people talking.

(2) Could का प्रयोग निम्नलिखित स्थितियों में किया जात है

1. शर्त वाचक
1. I could lift this box (if I tried).
2. I could buy a shirt (if I had money)

2. प्रार्थना वाचक
1. Could (Would) you tell me the time?
2. Could (Would) you bring me a glass of water ?

3. सम्भावना सूचक
1. One of the prisoners escaped yesterday. He could be anywhere now.
2. I could be in the USA by next year.

4. Can का Past
1. He said that I could go.
2. He could come to me any time he liked.

May तथा Might का प्रयोग 

(1) May का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. अनुमति / इजाज़त सूचक
1. You may go now.
2. May I come in, sir ?

2. सम्भावना सूचक
1. His statement may (can / could) be true.
2. His plan may (can / could) succeed.

3. इच्छा / प्रार्थना सूचक
1. May you live long !
2. May our country prosper !

(2) Might का प्रयोग निम्नलिखित स्थितियों में किया जाता है

1. May or Past
1. He said that I might go.
2. I thought that he might help her.

2. भावी सम्भावना
1. He might (may) pass this year.
2. He might (may) reach here by evening.

3. इजाज़त होना
1. Might I have your pen ?
2. You might do me a favour.
(May की अपेक्षा might में अधिक झिझक और विनम्रता का संकेत होता है।)

Must का प्रयोग

Must का प्रयोग निम्नलिखित स्थितियों में किया जाता है1. उपदेश सूचक
1. You must consult some good doctor.
2. You must work hard this year.

2. आवश्यकता सूचक
1. You must be back by evening.
2. The students must bring their books daily.

3. सम्भावना सूचक
1. The child must be hungry.
2. He must have made some big mistakes

4. बन्धन / मजबूरी सूचक …
1. You must do as you are told…
2. He must clear his accounts before leaving.

Ought to तथा Used to का प्रयोग

(1) Ought के साथ सदा to का प्रयोग किया जाता है।
(Ought to = Should)
Ought to का प्रयोग (should की भान्ति) निम्नलिखित स्थितियों में किया जाता है

1. नैतिक फर्ज़
1. You ought to respect your elders.
2. You ought to have helped the poor.

2. इच्छा-योग्य सम्भावना
1. Mohan ought to win the race this time.
2. You have worked hard. You ought to get good marks.

3. इच्छा-योग्य जरूरत
1. He ought to build a new house now.
2. There ought to be some more buses.
(इस तालिका में दिए गए सभी वाक्यों में ought to के स्थान पर should का प्रयोग किया जा सकता है।)

(2) Ought की भान्ति used भी एक ऐसा modal है जिसके साथ to का प्रयोग करना ज़रूरी होता है।
1. He used to live here.
2. He never used to live here.
3. Used he to live here ?

Need का प्रयोग

(1) Auxiliary के रूप में Need का प्रयोग केवल Negative और Interrogative वाक्यों में किया जाना
चाहिए। इसका प्रयोग किसी सन्देह (doubt) अथवा मनाही (prohibition) को ज़ोरदार ढंग से व्यक्त करने के लिए किया जाता है।
1. Need I go there ? No, you needn’t.
2. Need she come tomorrow ? No, she needn’t.

(2) Need का Third Person Singular सदा need ही होता है, न कि needs।
1. Need Mohan go there now ?
2. He need not worry any more.

(3) प्रश्नवाचक वाक्यों में need का प्रयोग तभी किया जाता है जब negative उत्तर वांछित हो।
Need you go there?
No, I needn’t.

(4) Interrogative और Negative वाक्यों में need के साथ to का प्रयोग नहीं किया जाता है।
Need he do any work?
No, he needn’t do any work.

Dare का प्रयोग

(1) Auxiliary के रूप में dare का प्रयोग निम्नलिखित स्थितियों में किया जाता है
1. Negative वाक्यों में।
2. Interrogative वाक्यों में।
3. सन्देह (doubt) व्यक्त करने वाले वाक्यों में।
4. ऐसे वाक्यों में जिन में hardly, never, no one, nobody का प्रयोग किया गया हो।

(2) जब dare का प्रयोग auxiliary के रूप में किया गया हो, तो इसके साथ to का प्रयोग नहीं किया | जाता है।
(3) Dare का Third Person Singular सदा dare ही होता है, न कि dares
Examples:
1. He dare not fight with me. (Negative)
2. Nobody dared ask him about his intentions. (Negative)
3. Dare he come to my house? (Interrogative)
4. I wonder whether he dare try. (Doubt)

Punjab State Board PSEB 10th Class Science Important Questions Chapter 13 Magnetic Effects of Electric Current Important Questions and Answers.

PSEB 10th Class Science Important Questions Chapter 13 Magnetic Effects of Electric Current

Long Answer Type Questions

Question 1.
Give magnetic field due to solenoid. On what factors the strength of the field depends?
Or
What is solenoid? How does a solenoid behave like a bar magnet?
Answer:
Solenoid. A solenoid is a long circular coil containing a large number of close turns of insulated copper wire.
Magnetic field due to solenoid. When an electric current is passed through the solenoid, it produces magnetic field around it as shown in Figure. Magnetic field produced by a current carrying solenoid is similar to the magnetic field produced by a bar magnet. The magnetic lines enter from one end of the solenoid and leave at the other end. If we look from left end, the current appears to be passing in the solenoid in clockwise direction and hence it acts as a south pole according to clock rule. If the solenoid is viewed from right side, the current appears to be in anticlockwise direction. Hence, right hand side face of the solenoid behaves as if this were a north pole.

Magnetic field due to current carrying solenoid is similar to bar magner.

Since the current flows in the various turns of the solenoid in the same direction, the magnetic field produced by each turn of the solenoid adds up, giving a very strong resultant field inside the solenoid.
Hence, a solenoid may be used in making electromagnets.

The strength of the magnetic field produced depends upon the following three factors :

1. Number of turns. The more the number of turns, the stronger will be the magnetic field produced.
2. Strength of the current in the solenoid. Larger the current, stronger will be the magnetic field produced.
3. Nature of core of solenoid. The strength of the field depends upon the core on which the coil is wound. For air core, field is very weak whereas for soft iron-core, the field is very strong. .

Question 2.
What is an electromagnet? Upon what factors its strength depends?
Answer:
Electromagnet: The combination of soft iron core and a current carrying insulated copper wire wound over it is called an electromagnet.
Very strong electromagnets can be produced by winding an insulated copper wire on a soft iron core.
When current is passed through a solenoid, a magnetic field is produced. Now if a soft iron core is placed inside the solenoid, the strength of the magnetic field becomes very large. The reason for increase in magnetic field is due to the fact that iron gets magnetised by induction.

Electromagnet

A simple electromagnet is as shown in Figure. To make an electromagnet, a soft iron core is placed inside a solenoid having large turns of insulated copper wire. The two ends of the solenoid are connected to a battery and a key.

Electromagnet lifting a car.

Strength of electromagnet depends upon

• Number of turns. Strength of electromagnets is directly proportional to the number of turns.
• Current flowing. More the current flowing through the wire, stronger is the electromagnet.
• Length of the air gap. Lesser the length of air gap between poles, stronger is the electromagnet.
• Air gap between the poles of a U-shaped electromagnet is small, hence it is very strong

Question 3.
Explain principal, construction and working of D.C. generator.
Answer:
Electric Generator. It is a device that converts mechanical energy into electric energy. It only converts the form of energy into another form. In generator, mechanical energy is the input while electric energy is obtained as output.

Principle: Generator is based on the principal that “when a conductor cuts magnetic lines of force, then according to the Faraday’s, electromagnetic law, electromagnetic force (emf) is induced in it which makes induced current to flow in the circuit when the circuit is closed”.

Construction: A D.C generator has the following main parts :

• Armature: It consists of a coil ABCD in which an insulated copper wire is wound into number of turns around a soft iron core, called armature. It is fixed on an axis and is capable to rotate with steam or running water.
• Field Magnet: There are two strong pole pieces (electro magnet)-in which the coil is placed forms a field magnet. In small generators, permanent magnets while in big generators electromagnets are used.
• Slip Rings: At the ends of the coil two slip rings R₁, and R₂ are attached. These two work as commutators.
• Carbon Brush Split: Rings R₁ and R₂ soft touch against the carbon brushes B₁ and B₂. When the coil rotates the slip rings R₁ and R₂ in turn touch B₁ and B₂.
• From carbon brushes B₁ and B₂ electric current is taken to the load (output). In the diagram galvanometer is shown in place of load.

Working. When the coil rotated about its axis, then emf is induced in arms AB and CD of the coil. The direction of induced electromagnetic force can be determined by Fleming’s right hand rule.

Suppose in the beginning the coil is in vertical position with its arm AB in the lower position and CD in the upper position. When the coil is rotated about its axis then during the first half rotations the arm AB moves in the upward direction and CD in the downward direction. According to Fleming’s right hand rule the direction of induced current in arm AB will be from A to B and in CD it is from C to D.

The arm AB on reaching the upper most position begins to move downward while the arm CD would begin to move in the upward direction. Therefore, the direction of induced current in the arms AB and CD gets reversed but to keep the direction of current in the load (output) same, the split rings are used. In the second half of the rotation the end of the coil comes in contact with the split ring R2 and the end D touches the split ring Rx so that the direction of current remain same in the load.

Question 4.
Arrange an activity to show that current is produced due to change in magnetic field.
Answer:
Make a coil XY having large number of terms of insulated copper wire wound area as shown in the figure. Connect the ends of the coil to a sensitive galvanometer.

Now quickly bring N-pole of a bar magnet but see that it does not touch the coil. You will see deflection in the galvanometer which proves that current is flowing in the galvanometer. Note the direction of deflection in the galvanometer.

Now take away the magnet as shown in fig 13.20. Again you will notice deflection in the galvanometer but diis time the direction of deflection is opposite to the first. If we do not move the magnet and keep it stationary near the coil then there is no deflection in galvanometer. This experiment shows that when there is a relative motion between the coil and the magnet then current is induced in the circuit.

Question 5.
What are essential precautions to be used while using electricity?
Answer:
The following precautions should be observed while using electricity :

• Turn off all switches including main switch whenever sparking or fire is noticed.
• All connections must be tight. Wires must be covered with proper insulation of proper thickness. All joints must be covered with insulating tape of a good quality. Defective / switches should be immediately replaced.
• Fuses should always be connected to live wire. The earth wire must be connected to the body of electric appliance.
• Fuse must be of proper rating and should always be connected to live wire.
• Whenever repairs are needed, switch off main switch. If however , repairs need a direct handling of live wire, rubber gloves, rubber shoes and a plier with insulated handle should be used.
• If inspite of all the precautions, a person gets a shock due to accidental touching a live wire, one should try to provide such a person with support of some non-conducting material like wood, plastic or rubber. Never try to pull away person by your hand.
• Always put on dry rubber shoes while repairing the circuit.

Question 6.
What are magnetic field lines? How can the magnetic lines of force due to a bar magnetic be shown?
Answer:
Magnetic Field. The area of field around the magnet in which the force of attraction or repulsion due to magnet is experienced, is called Magnetic field.

Magnetic field lines: It is the path in the magnetic field, along which the unit N-pole would move when it is free to move.
magnet can be shown by the following two methods :
1. Place a magnet on a cardboard sheet. Now spread iron filings on the Cardboard and tap it gently will when the iron filings will arranged itself in the pattern of magnetic lines of force.

2. Drawing magnetic lines of a bar magnet Activity. Place a bar magnet on a white sheet and mark its boundary with pencil. Place a magnetic compass needle near the North-pole of the magnet. Now mark the position of poles of the magnetic needle with a sharp pencil. Now move the magnetic compass needle in such a position so that its S-pole is in the position of previous position of North-pole, Again mark position of N-pole with pencil. Repeat this process so that you reach south- pole of the bar magnet. Now join these marked points making a free hand curve.

This curve represents a magnetic line of force. In the same way by taking another point near the north pole of the bar magnet get different line of force. By taking various points and drawing different curve for each of the points you will get a pattern of magnetic lines of force due to a bar magnet.

Magnetic lines o force around a bar magnet.

Short Answer Type Questions

Question 1.
How will you prove that current flowing through a copper wire produces magnetic effect?
Answer:

• On passing current through a thick copper wire with a magnetic needle placed in its neighbourhood will be deflected.
• This shows that current flowing through a copper wire produces magnetic field all round it.

Question 2.
What do you understand by magnetic effect of current? To understand this effect give Oersted experiment.
Answer:
Magnetic Effect of Electric Current. When electric current flows through a conducting wire, then magnetic field is produced all round it. This effect of electric current is known as magnetic effect.

Oersted Experiment. Oersted took a conducting wire XY and placed a magnetic needle under this wire, then pressed the key and passed current through the wire in the direction from X to Y as shown in figure (a). He observed that the N-pole of the magnetic needle gets displaced towards west. Similarly, he repeated the experiment by reversing the direction of flow of current in the wire by changing the terminals of battery connected to the ends of the wire. This time the direction of deflection of the needle was opposite i.e. from Y to X as shown in figure (b).

The direction of deflection of magnetic needle can be remembered by ‘SNOW’ rule. This rule states that “If current in the wire XY flows from south pole to north pole when the current carrying conductor is placed above the conductor then the N-pole of the conductor gets displaced towards the west direction.”

Question 3.
Define magnetic field and write important properties of magnetic lines of force.
Answer:
Magnetic Field. It is the field or region around a magnetic in which the effect of magnet (force of attraction or repulsion) can be experienced.
Magnetic Lines of Force. The path on which a unit N-pole moves when it is free to move, is called magnetic line of force.

Important properties of magnetic lines of Force.

• Outside the magnet, magnetic lines of force start from north pole (N-pole) of the magnet and end at its south pole (S-pole).
• No two magnetic lines of force intersect each other and if they do so then it would mean that the point of intersection there are two directions of magnetic lines of force which is impossible.
• At any point or the magnetic field the direction of the field lines is along the tangent at that point.

Question 4.
How will you represent diagrammatically uniform and non-uniform magnetic field?
Answer:
The uniform magnetic field represented by equally spaced parallel lines while non-uniform magnetic field is represented either by non-parallel lines or by unequally spaced lines. These are shown in the diagrams below :

(i) Uniform magnetic field, (ii) and (iii) Non-uniform magnetic field.

Question 5.
In the given figure what are the lines shown around the magnet called? Also give any two properties of these lines.

Answer:
In the figure the lines shown around the magnet are called magnetic field lines.

Properties of magnetic field lines,

• Outside magnetic: the magnetic field lines start from the N-pole of the magnet and end at the S-Pole while inside the magnet the direction of magnetic lines are from S-Pole to the N-Pole.
• The direction of magnetic field at any point of the magnetic line of force is represented by the tangent drawn to the curve at that point.

Question 6.
What is Maxwell’s Right hand thumb Rule? For what purpose this rule is used?
Answer:
Maxwell’s Right Hand Thumb Rule According to this rule “To find the direction of magnetic field around a straight carrying conductor if the straight conductor is held in right hand in such a way that your thumb points in the direction of current then the curling fingers would determine. The direction of magnetic field lines.”

The rule is used to determine the direction of magnetic field lines produced around a straight conductor carrying current.

Question 7.
Which rule is shown in the figure? Define the rule. In which device this rule is used?

Answer:
Fleming’s Left Hand Rule is shown in the figure.

Fleming’s Left Hand Rule. According to this rule, stretch your left hand in such a way that the thumb, forefinger and central finger are mutually at right angle to each other. If the fore finger points in the direction of the magnetic and the central finger points in the direction of current, the thumb gives the direction of the force acting on the conductor.

This rule is used in the working of an electric motor.

Question 8.
Fleming’s left hand rule, Label the diagram.

Answer:
Fleming’s Left Hand Rule. According to this rule, stretch your left hand in such a way that the thumb, forefinger and central finger are mutually at right angle to each other. If the fore finger points in the direction of the magnetic and the central finger points in the direction of current, the thumb gives the direction of the force acting on the conductor.

This rule is used in the working of an electric motor.

1. Force acting on the conductor OR direction of motion
2. Direction of magnetic field
3. Direction of current

Question 9.
Name the law shown in the figure. Label 1 and 2 law.

Answer:
The figure represents Fleming’s Right Hand Thumb Rule

1. Magnetic Field
2. Current induced in the conductor.

Question 10.
In the alongside figure a straight conductor B is carrying current in the vertical downward direction.
(a) What will be the direction of magnetic field lines around the conductor?
(b) Name the law which you have used for your answer.

Answer:
(a) Clockwise.
(b) Maxwell’s Righthand Thumb Rule.

Question 11.
What is Electro-magnetic Induction?
Answer:
Electro-magnetic Induction. The process of producing e.m.f by changing the magnetic lines of force linked with the circuit, is called electromagnetic induction. The electromagnetic force (e.m.f) so produced is called induced electromotive force.

Question 12.
List some such electric appliances in which electric motor is used.
Answer:
With the help of electric motor all such appliance work in which it is required to produce rotatory in motion e.g. Electric fan, tape recorder, mixer etc.

Question 13.
What is Electric Fuse? What is its importance?
Answer:
Electric Fuse. It is a device used in electric circuits which prevents the other electric appliances connected in the circuit from being damaged by high current. It has low meeting point.

Importance (use) of Electric Fuse. If for some reason heavy current begins to flow in the circuit then fuse wire melts and breaks the circuit and accident is prevented.

Question 14.
Why the fuse wire should have high resistance and low melting point?
Answer:
The fuse wire should have high resistance and low melting point because when it is connected in series then heavy current will not flow through fuse wire due to its high resistance and the heat produced will melt it due to its low melting point. Thus the electric appliances connected in the circuit would be saved from damage.

Question 15.
What is meant by over-loading?
Answer:
Over-loading. Overloading means to draw large current from the mains. This happens when many appliances are connected with single socket simultaneously. The supply wires as well the wires used in household wiring has a specific rating. The rating of 15 A means that if a current upto 15A is passed through the circuit, there is no likely damage feared to the circuit. But if a current more than maximum allowed limit is passed, there may be excessive heating of the wires and it may damage the wiring.

Question 16.
When does an electric short-circuit occur?
Answer:
Short-circuiting. An electric circuit is said to be short-circuited if a live wire touches neutral wire or earth wire, a large current flows through the circuit due to almost zero resistance of the circuit. This results in increase of temperature and hence heating of wires which may cause fire or damaging the appliance.

To save the circuit from damage due to over-loading or short-circuiting, a fuse of proper rating is put in each circuit.

Question 17.
What are hazards of electricity?
Answer:
Hazards of Electricity. Electricity is the most important source of energy. A proper use of electricity is a boon while improper use is very dangerous and may prove to be fatal. There are number of hazards.

• If by accident a person touches a live wire, he gets a very severe shock which may prove fatal.
• Loose connections, defective switches and sockets can cause sparking which may lead to fire.
• Short circuiting due to damaged wires or overloading of circuits can cause fires.

Very Short Answer Type Questions

Question 1.
What is a dynamo?
Answer:
Dynamo. It is a device which converts mechanical energy into electric energy.

Question 2.
On what principle is an a.c. motor based?
Answer:
It is based upon Fleming’s left hand rule.

Question 3.
What is an electric motor?
Answer:
Electric motor. It is a device which converts electric energy into mechanical energy.

Question 4.
List three sources of magnetic field?
Answer:
Electromagnet, load stone, solenoid, bar magnet.

Question 5.
Name the physical quantity whose S.I. unit is weber/m2.
Answer:
Magnetic field.

Question 6.
In which part of a bar magnet, the magnetic field lines are more denser?
Answer:
At the poles of a magnet.

Question 7.
How does the strength of the magnetic field at the centre of a circular coil of a wire depend on : (a) radius of the coil (b) number of turns of the coil.
Answer:
(a) Strength of magnetic field (B) ∝ \(\frac{1}{\text { radius of the coil }(r)}\)
(b) Strength of magnetic field (B) ∝ Number of turns of the coil (N).

Question 8.
Name any two devices which uses electric motor as an essential component in their working.
Answer:

1. Water pump
2. Electric fan.

Question 9.
Define an electromagnet.
Answer:
Electromagnet. The combination of an soft iron core and current carrying insulated wire wound over it, is called an elctromagnet.

Question 10.
Define magnetic pole.
Answer:
Magnetic poles are points near the ends of a magnet where magnetic field is maximum,

Question 11.
Give a property of a Magnet.
Answer:
Directive Property (stays always in N-S directions, when suspended freely).

Question 12.
Name two electric devices which act on magnetic effect of electric current.
Answer:

1. Electric bell
2. Loud-speaker.

Question 13.
What is electric fuse?
Answer:
Fuse is a safety device which saves electric circuit from damage due to over loading a short circuit.

Question 14.
Which electrical phenomenon is responsible for deflection of galvanometer needle in the given figure?

Answer:
Electric Induction.

Multiple Choice Questions:

Question 1.
The direction of magnetic field produced on passing electric current in a conductor is determined by
(A) MaxweI1s Left hand rule
(B) Fleming’s right hand rult
(C) Fleming’s left hand rule
(D) Faraday’s law.
Answer:
(A) MaxweJi Left hand rule

Question 2.
The direction of the force produced in a current carrying coil placed in a strong magnetic field is determined by
(A) Maxwell’s right hand rule
(B) Fleming’s right hand rule
(C) Fleming’s left hand rule
(D) Faraday’s law.
Answer:
(C) Fleming’s left hand rule

Question 3.
What is the colour of neutral wire in a domestic electric circuit?
(A) Black
(B) Red
(C) Green
(D) No specific colour.
Answer:
(A) Black

Question 4.
When a current carrying wire and neutral wire come in contact so that heavy current begins to flow, this arrangement is called:
(A) Overloading
(B) Short circuit
(C) Earthing
(D) All the above.
Answer:
(B) Short circuit

Question 5.
Connecting metallic frame of high power electrical appliances with the earth wire of domestic circuit is called
(A) Overloading
(B) Short circuit
(C) Earthing
(D) Ail of these
Answer:
(C) Earthing

Question 6.
Which of the following is source of direct current?
(A) Dry cell
(B) Button cell
(C) Lead battery
(D) All these.
Answer:
(D) All these.

Question 7.
The device used for producing electric current is called a :
(A) Generator
(B) Galvanorneter
(C) Ammeter
(D) Motor.
Answer:
(A) Generator

Question 8.
Similar magnetic poles
(A) Attract
(B) Repel
(C) Both attract and repel
(D) None of these.
Answer:
(B) Repel.

Question 9.
Magnetic field lines are.
(A) Straight lines
(B) Curved
(C) Closed curves
(D) Triangular.
Answer:
(C) Closed curves

Punjab State Board PSEB 10th Class Science Book Solutions Chapter 13 Magnetic Effects of Electric Current Textbook Exercise Questions and Answers.

PSEB Solutions for Class 10 Science Chapter 13 Magnetic Effects of Electric Current

PSEB 10th Class Science Guide Magnetic Effects of Electric Current Textbook Questions and Answers

Question 1.
Which of the following correctly describes the magnetic field near a long wire? The field consists of :
(a) straight lines perpendicular to the wire.
(b) straight lines parallel to the wire.
(c) radial lines originating from the wire.
(d) concentric circle centred on the ware.

Answer:
(d) concentric circles centred on the wire (Figure)

Question 2.
The phenomenon of electromagnetic induction is :
(а) the process of charging a body.
(b) the process of generating magnetic field due to a current passing through a coil.
(c) producing induced current in a coil due to relative motion between a magnet and the coil.
(d) the process of rotating the coil of an electric motor.
Answer:
(c) producing induced current in a coil due to relative motion between a magnet and the coil.

Question 3.
The device used for producing electric current is called :
(a) generator
(b) galvanometer
(c) ammeter
(d) motor.
Answer:
(a) generator.

Question 4.
The essential difference between an AC generator and a DC generator is that:
(а) AC generator has an electromagnet while a DC generator has a permanent magnet.
(б) DC generator will generate higher voltage.
(c) AC generator will generate higher voltage.
(d) AC generator has slip rings while the DC generator has a commutator.
Answer:
(d) AC generator has slip rings while DC generator has a commutator.

Question 5.
At the time of short circuit, the current in the circuit.
(a) reduces substantially
(b) does not change
(c) increases heavily
(d) vary continuously.
Answer:
(c) increases heavily.

Question 6.
State whether the following statements are true or false.
(a) An electric motor converts mechanical energy into electric energy.
(b) An electric generator works on the principle of electromagnetic induction.
(c) The field at the centre of a long circular coil carrying current will be parallel straight lines.
(d) A wire with a green insulation is usually the live wire.
Answer:
(a) is false. It converts electric energy to mechanical energy.
(b) is true.
(c) is true.
(d) is false. Green is usually earth wire.

Question 7.
List three sources of magnetic field.
Answer:
Sources of Magnetic field are :

• Magnet.
• Current carrying conductor
• Current carrying solenoid.

Question 8.
How does a solenoid behave like a magnet? Can you determine north and south poles of current carrying solenoid with the help of bar magnet? Explain.
Answer:
Solenoid: It consists of a coil of a number of turns of insulated copper wire closely wound in the shape of a cylinder. Magnetic field around a current carrying solenoid is shown in Figure.

Field lines of the magnetic field inside and around a current carrying solenoid.

These magnetic lines due to current carrying solenoid appear to be similar to that of a bar magnet shown in Figure.

One end [right end] of solenoid behaves like north pole and the other end [left end] behaves like south pole. Magnetic field lines inside the solenoid are in the form of parallel straight lines. This means that the field is the same at all points inside the solenoid.

Field lines around a bar magnet.

A soft iron rod when placed inside the solenoid behaves, like an electromagnet.

Question 9.
When is, the force experienced in a magnetic field, the largest?
Answer:
When the field is perpendicular to current carrying conductor, the force experienced by a current carrying conductor placed in a magnetic field is largest.

Question 10.
Imagine that you are sitting in a chamber with your back to one wall. An electron beam moving horizontally with back towards the front wall, is deflected by a strong magnetic field to your right side. What is the direction of the magnetic field?
Answer:
The magnetic field will be acting in vertically downward direction in accordance with Fleming’s left hand rule. [Direction of the current should be considered in a direction opposite to the direction in which the electrons move].

Question 11.
Draw a labelled diagram of an electric motor. Explain its principle and working. What is the function of a split ring in electric motor?
Answer:
Electric motor: It is a device which is used to convert electric energy into mechanical energy.
Principle, “When a current carrying coil is placed in a uniform magnetic field, it experiences a torque which rotates the coil.”

I indicates direction of current; F the direction field and M the direction of motion

Working: A direct current from a battery is passed through armature. The current flows in the coil along ABCD as shown in Figure (a). The limb AB of the coil experience downward and CD of the coil experience upward force in accordance with Fleming’s left hand rule. These two equal and opposite forces constitute a couple tending to rotate the coil in clockwise direction. After half the rotation, brush B₁ has contact with S₂ and brush B₂ with S₁. The direction of the current gets reversed. The current now flows along DCBA instead of along ABCD. Limb DC experiences downward and BA experiences an upward force in accordance with Fleming’s left-hand rule.

The process repeats itself and motion of armature becomes continuous after some time.
Functions of Split rings. They help in reversing the direction of current in the coil after every half rotation.

Question 12.
Name some devices in which electric motors are used.
Answer:
Electric motor are used in battery operated toys, in tape recorder, in car fans, mixers, grinders, computers and variety of other electric appliances.

Question 13.
A coil of insulated copper wire is connected to a galvanometer. What will happen if a bar magnet is (i) pushed into the coil; (ii) withdrawn from inside the coil; (iii) held stationary in the coil?
Answer:

• When the bar is pushed into the coil, there will be momentary deflection of galvanometer in one direction. This is so because when magnet is brought near the coil, magnetic lines linked with the coil increases, so that induced emf is produced which induces current in the coil.
• Faster, we push the magnet, more will be the deflection.
• When the bar magnet is withdrawn, there will again be momentary galvanometer deflection but in a direction opposite to that when magnet was pushed in. This time also current is induced in the coil.
• When the magnet is held stationary inside the coil, there will be no deflection in galvanometer. It is because no emf is induced and hence no current is induced in the coil.

Question 14.
Two circular coils A and B placed closed to each other. If the current in the coil A is changed, will some current be induced in coil B? Give reason.
Answer:
If the current in the coil is changed (switched on or switched off), then an electric current is induced in coil B. ‘

It is because when, plug in the key is introduced, current flows through the coil ‘A’ so that magnetic field is produced all round it. These magnetic lines produced in the coil ‘A’ will pass through the coil ‘B’ with the result induced emf and hence induced current is produced in the coil ‘B’ which is indicated by deflection of the galvanometer. Now when plug is removed from the key (switched off) the magnetic lines of force Jinked with the coil ‘B’ again change (decreases). This time again current is induced in the coil ‘B’.

Question 15.
When does an electric short circuit occur?
Answer:
Electric short-circuit occurs when :

• live wire incidently touches neutral or earth-wire.
• insulation around the current carrying wires is weak.
• insulation gets hardened by the excessive use.
• current passed through wire is more than its rating.

Question 16.
What is the function of earth wire? Why is it necessary to earth metallic appliances?
Answer:
Earth wire. It is used as a safety measure especially for electric appliance having metallic body. The metallic body of appliances like electric press, fans, toasters, refrigerators etc. are connected to earth wire which provides an easy path for current to go to the earth in case live wire touches the body of appliance incidently. The user will not suffer a severe electric shock in the event of touching a defective appliance.

Question 17.
State two properties of magnetic field lines.
Answer:

1. Magnetic field start from north and end at south.
2. They never intersect each other.

Science Guide for Class 10 PSEB Magnetic Effects of Electric Current InText Questions and Answers

Question 1.
Why does a compass needle get deflected when brought near a bar magnet?
Answer:
A compass needle is a small bar magnet with one end as north and the other end as south pole. It is a well known fact that similar poles repel each other and dissimilar poles attract each other. When N-pole of a bar magnet is brought near the compass, the north pole of compass gets repelled while its S-pole is attracted so that compass needle gets deflected.

Question 2.
Draw magnetic lines around a bar magnet.
Answer:
Place a bar magnet in the middle of a sheet of paper fixed on drawing board by using adhesive tape. Mark the boundary of the magnet with pencil. Place compass near north pole of the magnet when south pole of the compass will point towards north pole of the magnet. Mark the two points a, b at the two ends of the needle. Move the needle to a new position such that S-pole of compass needle is at b [position previously held by N-pole].

Repeat this till you reach south pole of the magnet (Figure).

Drawing magnetic field lines by compass needle.

Now Join the marked points on a paper by a smooth line which gives one magnetic line of force as shown in Figure. Repeat this procedure taking Figure Magnetic field around a bar different starting points.

Magnetic field around a bar magnet.

Question 3.
List the properties of magnetic lines of force.
Or
Write characteristics of magnetic field lines.
Answer:
Properties (characteristics) of magnetic lines of force are :

• These are the closed curves passing through the magnet. Outside the magnet lines of force start from north pole of the magnet and end at the south pole and inside the magnet, the direction of magnetic lines are from south pole to north pole.
• The two magnetic lines of force never intersect each other.
• They have a tendency to contract lengthwise which explains the attraction between opposite poles.
• The tangent at any point of the magnetic lines of force gives the direction of the field at that point.
• They exert lateral pressure upon each other, which explains repulsion between like poles.

Question 4.
Why two magnetic lines of forces never intersect each other?
Answer:
No two magnetic lines of force cross each other because, if they did so, then at the point of intersection; the compass needle would point towards two directions at the same time, which is not possible. Hence two magnetic lines never intersect each other.

Question 5.
Consider a circular loop of wire lying in the plane of the table. Let the current pass through the loop clockwise. Apply right hand rule to find out the direction of the magnetic field inside and outside the loop.
Answer:
The direction of the magnetic field inside and outside loop is as shown in Figure. By applying right hand rule we find that the direction of magnetic field inside the loop is downward normally and outside the loop it is normal to the plane of paper.

Question 6.
The magnetic field in a given region is uniform. Draw a diagram to represent it.
Answer:
Uniform magnetic field is shown by equidistant and parallel lines as shown in Figure If the parallel lines are close to each other, the field is strong. The stronger the field, the closer are the lines.

Question 7.
Choose the correct option.
The magnetic field inside a long straight solenoid carrying current (a) is zero ;
(b) decreases as we move towards end ;
(c) increases as we move towards end;
(d) is same at all the points.
Answer:
(d) is correct. The magnetic field inside a long straight solenoid is same at all the points.

Question 8.
Which of the following property of proton can change while it moves freely in a magnetic field? [There may be more than one correct answer].

(a) mass
(b) speed
(c) velocity
(d) momentum.
Answer:
(c) Velocity and (d) Momentum.

Question 9.
In activity shown, how do you think the displacement of rod AB will be affected :
(i) if the current in rod AB is increased;
Answer:
Since force acting on the rod is directly proportional to the current passing through it. Therefore, the displacement will be increased when current is increased.

(ii) a stronger horse shoe magnet is used;
Answer:
Stronger the magnet, more will be the force and hence the displacement.

(iii) length of the rod AB is increased.
Answer:
Force is also directly proportional to the length of the rod. Hence rod will be displaced more if the length is increased.

Question 10.
A positively charged particle emitted from a nucleus alpha particle projected towards west is deflected towards north by a magnetic field. The direction of the magnetic field is :
(a) towards south
(b) towards east
(c) downward
(d) upward.
Answer:
(d) upward [In accordance with Fleming’s left hand rule]

Question 11.
State Fleming’s left hand rule.
Answer:
Fleming’s left hand rule. It states, “Stretch the thumb, fore finger and middle finger of your left hand such that they are mutually perpendicular to each other. If the first finger points in the direction of magnetic field and central (second) finger points towards the direction of current then thumb points towards the direction of motion as shown in Figure.

Flemmgs left hand rule for direction of force on current carrying conductor

Question 12.
What is the principle of an electric motor?
Answer:
Principle of Electric motor. Electric motor is based upon the principle that when a current carrying coil is placed in a uniform magnetic field, it experiences torque which rotates the coil.

Question 13.
What is the role of the split ring in an electric motor?
Answer:
The split rings act as a commutator in D.C. motor i.e., it reverses the direction of current through the circuit after every half cycle.

Question 14.
Explain different ways to induce current in a coil.
Answer:
There are mainly two methods to induce current in a coil.

Induced current due to relative motion between coil and magnet.

When the magnet is stationary [at rest as in Figure (a)], no induced current is produced.
1. When magnet is moving with its N-pole towards the coil, deflection in galvanometer is as shown in Figure (b). Direction of the current gets reversed when N-pole is withdrawn from inside the coil (going away from coil) as shown in Figure (c). Faster the magnet moves, more is the deflection and hence current in galvanometer.

Deflection produced in the galvanometer needle by the current is same when N-pole was moving down [Figure (6)] or when south pole is out of the coil [Figure (e)].

Current and hence deflection in the galvanometer needle will be again produced if magnet is kept at rest and coil is moved.

2. By changing current in the neighbouring circuit. Take a non¬conducting cylindrical tube (say of card board). Wind two set of coils I and. II on it as shown. Connect a battery and a key to the ends of coil I and a galvanometer to the ends of coil II. When plug is inserted in key K, there will be an instantaneous deflection m galvanometer even though there is no cell in this circuit. Now take out the plug from key K. An instantaneous large deflection in opposite direction to previous deflection will be produced in galvanometer. Thus current has been induced in coil II due to increase or decrease of current in coil I.

Induced Current by changing current m the neighbouring circuit.

Question 15.
State the principle of electric generator.
Answer:
Principle of Electric Gen¬erator. Electric generator is based upon Fleming’s right hand rule.

Right hand rule

Fleming’s right hand rule. Stretch the thumb, fore-finger, control (middle) finger of right hand so that they are perpendicular to each other. If fore-finger indicates the direction of magnetic field, the thumb shows the direction of motion of the conductor, the central (middle) finger will show the direction of induced current.

Question 16.
Name some sources of direct current.
Answer:
Sources of direct current are

• Cell
• Battery
• D.C. generator.

Question 17.
Which sources produce alternating current?
Answer:
Alternating current is produced by A.C. generators. There are hydro-generator and thermal generators.

Question 18.
Choose the correct option :
A rectangular coil of copper wires is rotated in magnetic field. The direction of induced current changes once in each:
(a) two revolutions
(b) one revolution
(c) half revolution
(d) one-fourth revolution.
Answer:
(c) half rotation.

Question 19.
Name two safety measures commonly used in electric circuits and appliances.
Or
Write the two safety measures commonly used in electric circuit appliances.
Answer:
Common Safety Measures used in Electric Circuits. Two most common safety measures used, are :

• A safety fuse of proper rating connected in a circuit prevents damage to the electric appliances and also the circuit due to overloading or short circuiting.
• Earth wire prevents possible electric shock when live wire incidently touches the body of appliance.

Question 20.
An electric oven of 2kW power rating is operated in a domestic electric circuit (220 V) that has a current rating of 5 A. What result do you expect? Explain.
Answer:
Given : Power of oven (P) = 2 kW
= 2,000 W
Voltage (V) =220 volts
Current (I) =?

We know that, P = V x I
or I = \(\frac{\mathrm{P}}{\mathrm{V}}\)
Current (I) = \(\frac{2,000}{200}\)
= \(\frac{100}{11}\)
= 9.09 A

A current of 9.09 A will flow in the circuit. Since the current rating of circuit is 5 A, the fuse (of 5 A) rating if inserted in the circuit will burn up. If no fuse is placed in the circuit, there may be a fire.

Question 21.
What precautions should be taken to avoid the overloading of domestic electric circuits?
Answer:
Precautions to avoid overloading.

• Wires used for carrying current should be of proper current rating. Whereas wire of low current rating may be used for lighting electric bulbs, tubes, T.V. etc., and wires of higher current rating should be used for A.C., heating appliances etc.
• There should be a separate circuit for heating appliance.
• PVC of good quality should be used for insulating wires.
• Each circuit should have a fuse of proper rating.
• After every 3-4 years wires should be replaced by new wires of proper rating.

Punjab State Board PSEB 10th Class Science Important Questions Chapter 12 Electricity Important Questions and Answers.

PSEB 10th Class Science Important Questions Chapter 12 Electricity

Long Answer Type Questions

Question 1.
(a) What is meant by Joule’s heating effect due to flow of current through a conductor?
Answer:
The conductors offer some resistance to the flow of current. If I is the current in ampere flowing for t second, then quantity of charge Q = I × t.

The work done in carrying a charge Q ( It). coulomb against a potential difference of
1 volt. W = V × Q
or W = V × It
= VIt joule

The whole of this energy is converted into heat.
∴ Heat produced, H = W = VIt joule ……….. (i)

Now V = IR
H = (IR)It joule
or H = I²Rt joule ………. (ii)
Again
I = \(\frac{V}{R}\)
∴ H = \(\frac{\mathrm{V}^{2}}{\mathrm{R}^{2}}\) Rt joule
or H = \(\frac{\mathrm{V}^{2}}{\mathrm{R}}\) t joule ………….. (iii)

Thus, when current is passed through a conductor, the heat produced is given by;
H = VIt = I²Rt = \(\frac{\mathrm{V}^{2}}{\mathrm{R}}\) t
and is called Joules heating effect.

(b) Define electric power and unit of electric power.
Answer:
Electric Power: The rate of doing electric work is called electric power. Suppose ‘V’ is the potential difference between the ends of a conductor and T is the current flowing through it,

Work done by flow of current T for ‘t’ second, W = VIt

Unit of Electric Power. We know P = V x I. If potential difference V is measured in volt and current T in ampere than power will be in watt.
1 watt = 1 volt x 1 ampere

The bigger unit of power is Kilowatt (kw)
1 kilowatt = 1000 watt.

(c) What do you mean by electric energy? Give the definition of its unit.
Answer:
Electric Energy: Total work done by electric current in a fixed time is called electric energy.

Suppose I ampere of current flows through a conductor for t seconds when the potential difference across the ends of a conductor is V, then total work done or electric energy consumed,
E = W = V × I × t

The unit of electric energy is joule or watt-second but this is a small unit.
The bigger unit of electric energy is watt hour.

Watt hour. The electric energy consumed in a circuit is said to be watt hour if 1 ampere of current flows for 1 hour and potential differenc across the ends is 1 volt.
1 watt-hour = 1 watt × 1 hr.
= 1 volt × l ampere × 1 hour 1 kilowatt hour (kwh) = 1000 watt hours
The bigger (commercial) unit of electric energy is kilowatt hour (kwh).

Question 2.
What is meant by resistance of a conductor? On what factors does the resistance of conductor depends?
Answer:
Resistance of Conductor. It is defined as the ratio of potential difference across its ends to the current flowing through the conductor is called resistance of the conductor. It is denoted by ‘R’.

If V is the potential difference between the ends of the conductor and T is the current flowing through the conductor, then
Resistance (R) = \(\frac{\text { Potential Difference }(\mathrm{V})}{\text { Current }(\mathrm{I})}\)

Unit of Resistance. S.I. unit of resistance is ohm.

Factors on which resistance of conductor depends.

• Electric source (i.e. battery or cell)
• Conductor
• Switch (or key)
• Any other instrument connected in the circuit.

Question 3.
Find experimentally the various factors on which resistance of conductor depends.
Answer:
On what factors the resistance of a conductor depends is shown by the following experiment :

Experiment: Arrange an electric circuit consisting of a battery, ammeter, connecting wire and conductor with the help of a switch (key). Press the switch and allow the current to flow through the circuit. Note the value of current from the ammeter. Now in place of this wire, connect another wire of place of this wire, connect another wire of same length and thickness and note the reading of ammeter. You will find that the value of current changes. This experiment shows that resistance of conductor depends upon the nature of material of wire i.e. at the same temperature the resistance of different conductors of same length and thickness is different.

Now take a wire of the same material as that of the first conductor and same diameter but of double length. Connect this wire in the same circuit and allow the current to flow through it. You will see this value is half of the first value. This shows that resistance is proportional to the length. If R is the resistance of the conductor and l the length then,
R ∝ l …(i)
Now take two wires of the same material but of different areas of cross section. At first connect a wire of small cross-section in the circuit and then replace it with a wire of large area of cross-section. Note the value of current I in two cases. You will see that more current flows in the second wire than in the first wire. It is clear that resistance of second wire is less than the first wire.
i.e. R ∝\(\frac{1}{A}\) ……(ii)

Combining (i) and (ii), we get
R ∝\(\frac{l}{A}\) …..(iii)
or R = ρ. \(\frac{l}{A}\) …(iv)
where ρ is a constant and is called resistivity of the conductor. Its value depends upon the nature of material of conductor (wire).

Question 4.
What is Ohm’s law? How can it be verified?
Or
Write ohm’s law. Draw a circuit diagram to prove it experimentally in the laboratory,
Answer:
Ohm’s law. It states that the current passing through a conductor is directly proportional to the potential difference across its ends provided the temperature and other physical conditions remains unchanged.
I ∝ Y
i.e. V ∝ I
or V = RI
Where R is a constant of proportionalty called resistance.

Resistance. It is the property of a conductor to oppose the flow of current. Resistance depends upon the nature of the conductor, its temperature and its dimensions (length, area).
R = \(\frac{V}{I}\)
or I = \(\frac{V}{R}\)
Experimental Verification of Ohm’s Law: Connect an ammeter, battery, key and rheostat as shown in Fig. 12.7(a). Put the plug in the key K. Read the values of potential difference across resistor R with the help of voltmeter V and the current flowing through the resistor with the help of ammeter.

Note the readings. Vary the current in the circuit by sliding contact of rheostat and go on noting reading in voltmeter and ammeter. Take the ratio potential difference (V) and corresponding value of current (I) each time. The ratio would be same, which proves Ohm’s law. Now plot a graph between V and I on graph paper. It will be straight line graph as shown in Figure (b) which also verifies that V ∝ I.

Question 5.
What is the need of combining different resistors? What is the resultant resistance when a number of resistances are connected in series?
Or
State Ohm’s law. Find the equivalent of resistances of the individual resistances connected in series.
Answer:
Ohm’s law: It states that the current passing through a conductor is directly proportional to the potential difference across its ends provided the temperature and other physical conditions remains unchanged.
I ∝ Y
i.e. V ∝ I
or V = RI
Where R is a constant of proportionalty called resistance.

Combination of Resistors: Resistors of all values of resistances are not available. Hence resistors are connected in a number of ways to increase or decrease the combined resistance. There are two distinct ways in which resistors can be connected. They are (i) resistors in series and (ii) resistors in parallel.

Resistors Connected In Series:

Resistors are said to be connected in series, if they are joined end to end so that the same current flows through each one of them in succession. Let the resistors R1( R2 and R3, be joined in series and let the current passing through them be I [Figure].

Let V₁, V₂, and V₃ be the potential difference between the ends of the first, second and third resistor respectively.
By Ohm’s law,
V₁ = IR₁; V₂ = IR₂ and V₃ = IR₃

If V is the total potential difference between the ends A and D and R is the effective resistance of the combination of all the resistors, then
V = IRS
But V = V₁ + V₂ + V₃.
or IR_s = IR₁ + IR₂ + IR₃
IR_s = I(R₁ + R₂ + R₃)
or R_s = R₁ + R₂ + R₃

The above result holds good for any number of resistors joined in series.
Thus when resistors are joined in series, the total resistance is equal to the sum of individual resistances.

Question 6.
With the help of a diagram derive the formula for the equivalent resistance of three resistances connected in parallels.
Or
With the help of a labelled circuit diagram derive a formula to find combined resistance (R) when two or more resistances (R₁, R₂, R₃) are connected in parallel taking symbols potential difference (V) and current (I).
Answer:
A circuit in which two or more resistors are connected across two common points so as to provide separate paths is called parallel circuit.

In this case, the same potential difference will be maintained between the two ends of every resistor and the current will divide itself in various branches.

Let the resistors R₁; R₂ and R₃ be joined in parallel between the points A and B.
Let the current I reaching A divide itself into three parts I₁; I₂ and I₃ along R₁, R₂ and R₃ respectively. Let V be the potential difference between the points A and B.

The currents flowing in the individual resistors are then given by :
I₁ = \(\frac{V}{R_{1}}\),
I₂ = \(\frac{V}{R_{2}}\) and
I₃ = \(\frac{V}{R_{3}}\)
Let R_p be the resistance of the combination,

The result holds good for any number of resistances.

Question 7.
What is meant by electric power? Give its units. Also give its SI unit.
Or
What is power? Give commercial unit of power.
Or
What is electric energy? What is its SI unit?
Answer:
Power is the rate of doing work. The electric power of an appliance is its rate of consumption of electric energy.
The power of an electric appliance is 1 W (watt) if it consumes 1 J (joule) of energy in 1 second.

If I ampere of the current flows for t second through a coil whose ends are maintained at a potential difference of V volt, then the energy consumed or the work done.
W = VIt joule

Power = \(\frac{\mathrm{W}}{t}\)
= \(\frac{\mathrm{VI} t \text { joule }}{t \text { second }}\)
or P = V × I joule/second
or = VI watt
∴ P (watt) = V (volt) × J (ampere)
or watt = volt × ampere

Bigger unit of power is usually kW (kilowatt)
1 kW = 1,000 W
P(in kW) = \(\frac{\text { watt }}{1,000}=\frac{\mathrm{V} \text { (volt) } \times \mathrm{I} \text { (ampere) }}{1,000}\)

Electric energy is the total amount of work done by the current in a given time or electric energy is the total amount of energy consumed in an electric circuit in a given time.
W (joule) = P(watt) × t (second)
or W = P\(\left(\frac{\mathrm{J}}{\mathrm{s}}\right)\) × t (s)
= P × t joule
But P = VI
∴ W = VIt joule

Practical Unit of Electric Energy: Practical unit of electric energy called kWh (kilowatt-hour) is usually used. This unit is also called B.O.T. (Board of Trade Unit).

The unit kWh is equal to the work done or energy consumed when a power of IkW is consumed for 1 hour.
Energy in kWh = \(\frac{\text { watt } \times \text { hour }}{1,000}\)
or
Energy in kWh = \(\frac{\text { volt } \times \text { ampere } \times \text { hour }}{1,000}\)

Short Answer Type Questions

Question 1.
What is the contribution of electricity in our daily life?
Answer:
Contribution of Electricity in our Life. Electricity finds great contribution in our life. It gives many facilities like its use in electric bulb and tubelight removes darkness at night, in summers with its use desert coolers and air conditioners keep our houses cool while in winters with its use in heaters we keep our houses warm. Besides this electricity is used in televisions, radios and cinemas for our entertainment. Electricity is also used to work the various machines the fields of agriculture, transport and industry.

Question 2.
What do you understand by static electricity?
Answer:
Static Electricity: When two bodies are rubbed against each other then they acquire a property to attract lighter bodies towards them that is they get static charge. Electricity produced by rubbing the two bodies with each other is called frictional electricity or static electricity. And the study of static charges is called electrostatics.

Example: When a plastic pen is rubbed with dry hair then the pen attracts small bits of paper towards itself. This is due to the electricity produced by rubbing.

Question 3.
What are positive and negative charges? How are these produced?
Answer:
Positive charge: The charge produced in glass rod when it is rubbed with silk cloth is called positive charge.
Negative charge: The charge produced on ebonite rod when it is rubbed with cat skin is called negative charge.

Question 4.
What is an electric circuit?
Answer:
Electric circuit. It is a closed path through which the electrons flow readily. When a conductor is connected to a battery, the electrons move from negative terminal of the battery to the positive terminal. However, conventionally, the current is considered to flow from positive to negative terminal of battery.

Question 5.
Distinguish between good conductors, resistors and insulators.
Answer:

• Good Conductors: Those substances through which the current can flow freely.
• Insulators: Those substances which do not allow the current to flow through them.
• Resistors: These are objects which oppose the flow of current through them.

Question 6.
What is meant by electric potential? Distinguish between positive potential and negative potential.
Answer:

• Electric Potential. It is the . specific electric state of conductor which tells us the directions of flow of charge when it is brought in contact with some other conductor. The potential of a conductor is determined relative to the potential of earth.
• Positive Potential: If positive charge flows from a body to earth or the flow of electrons is from earth to the body then the potential of the body is said to be positive potential.
• Negative Potential: The body is said to have negative potential if negative charge either flows from earth to body or electrons flow from body to earth.

Question 7.
What is electromotive force (emf) of a cell?
Answer:
Electromotive Force of Cell. The energy consumed by the cell connected in the circuit in making a unit charge to flow in the circuit is called electromotive force (emf) of the cell.
The S.I. unit of emf is volt.

Question 8.
What is the potential difference between two points in the electric field? Name and define its SI unit.
Answer:
Let a charge Q be moved from one point to another point, in the electric field and W be the work done, then the potential difference V between two points is given by :
V = \(\frac{\mathrm{W}}{\mathrm{Q}}\)
or W = VQ
If Q = + 1C, then V = W

Definition: The potential difference between two points in the electric field is defined as the amount of work done in moving a unit positive test charge from one point to the other against electrostatic force due to electric field.

SI units of P.D. is volt: Potential difference between two points is said to be 1 volt if 1 J of the work is done in moving a charge of 1 C from one point to the other.
Hence 1 volt = \(\frac{1 \text { joule }}{1 \text { coulomb }}\)
1 V =1 J/C
= 1 JC-1

Question 9.
Define Volt. It is a unit of which physical quantity?
Answer:
Volt: The potential difference between two points in an electric field is said to be 1 volt when 1 joule of work is done in carrying 1 coulomb of charge from one point to the other against the electric force.
1 volt = \(\frac{1 \text { joule }}{1 \text { coulomb }}\)

Volt is the unit of physical quantity, potential difference.

Question 10.
How can we say that electric current is due to flow of charge?
Answer:
If we connect an uncharged electroscope with a charged electroscope with the help of a wire then charge flows from a charged electroscope to an uncharged electroscope and the leaves of uncharged electroscope diverge. This flow continues up till the time the leaves of two electroscope become equally diverged. This flow of charge is called current.

Question 11.
What is meant by electric current?
Or
What is electric current?
Answer:
Electric Current: When two points at different potentials are connected with each other with a copper wire then charge begins to flow from point at a higher potential to a point at lower potential. This process continues till the potential of two points become same. If there remains a potential difference between two points then the flow of charge continues. In this way the flow of charge constitutes electric current.

Question 12.
How does electric current produce heat?
Answer:
In a metallic conductor there are present large number of free electrons moving freely in haphazard direction. When the conductor is connected to an electric source then free electrons flow from high potential to low potential when these electrons collide with atoms of the conductor. Due to this collision kinetic energy of electrons gets transferred to atoms of the conductor. This results in increase of kinetic energy of the atoms so as to increase the temperature of the conductor and hence heat is produced in the conductor.

Question 13.
Define resistance of conductor. Also give its units.
Or
What is meant by resistance of conductor. Define its units.
Answer:
Resistance of Conductor. It is defined as the ratio of potential difference across its ends to the current flowing through the conductor is called resistance of the conductor. It is denoted by ‘R’.

If V is the potential difference between the ends of the conductor and T is the current flowing through the conductor, then
Resistance (R) = \(\frac{\text { Potential Difference }(\mathrm{V})}{\text { Current }(\mathrm{I})}\)

Unit of Resistance. S.I. unit of resistance is ohm.

ohm: Resistance of a conductor will be 1 ohm if potential difference between its ends is 1 volt and the current flowing through it is 1 ampere.
That is, it is the resistance of a metallic cube whose each side is 1 m and current of 1 ampere flows perpendicularly across its opposite faces.

Question 14.
What is meant by resistivity? Write its S.I. unit and give its importance.
Answer:
Resistivity: From Ohm’s Law we know that,
R = ρ\(\frac{l}{A}\)
If I = lm and A = 1 m², then
R = ρ

So, resistivity of a material of a conductor is the resistance offered by its material to the flow of current of 1A if the length of the conductor is 1 m and its area of cross section is 1 m2.
Its S.I. unit is ohm meter (Ω m).

Importance :

• It changes with change in temperature.
• The materials having high resistivity are bad conductors of electricity. Examples. Plastic, Rubber etc.
• The materials having low resistivity are good conductors of electricity. Examples. Metals, Alloys etc.
• Resistivity of an alloy is more than the resistivity of any of its constituents.

Question 15.
What is electric current ? Give its unit in S.I. system.
Answer:
Electric Current. The directed flow of electrons per unit time is called electric current. It is denoted by T.
Or
It is also defined as the ratio of flow of charge per unit time.
Electric current = \(\frac{\text { Charge }}{\text { rime }}\)
I = \(\frac{\mathrm{Q}}{t}\)

S.I unit of current is ampere (A)
1 ampere = \(\frac{1 \text { coulomb }}{1 \text { second }}\)
where 1C = \(\frac{1}{1.6 \times 10^{-19}}\) electrons
= 6.25 × 10¹⁸ electrons

Ampere: If 1 coulomb of charge is allowed to flow through a conductor in 1 second, then the current flowing through the conductor is said to be 1 ampere.

The smaller unit of current is milli 1 ampere
1 milliampere = \(\frac{1}{1000}\) ampere
= 10^-3 ampere

Question 16.
Name and define unit for electric current?
Answer:
The unit of electric current is Ampere.
Ampere: If 1 coulomb of charge is allowed to flow through a conductor in 1 second, then the current flowing through the conductor is said to be 1 ampere.

The smaller unit of current is milli 1 ampere
1 milliampere = \(\frac{1}{1000}\) ampere
= 10^-3 ampere

Question 17.
What is electric energy? What is its SI unit?
Answer:
Electric energy. It is the total amount of work done by the current in a given time or electric energy is the total amount of energy consumed in an electric circuit in a given time.
W (joule) = P(watt) × t (second)
or W = P\(\left(\frac{J}{s}\right)\) × t (s)
= Pt joule
But P = VI
∴ W = VIt joule

Practical Unit of Electric Energy: Practical unit of electric energy called KWh (kilowatt-hour) is usually used. This unit is also called B.O.T. (Board of Trade Unit).

The unit KWh is equal to the work done or energy consumed when a power of 1KW is consumed for 1 hour.
Energy in KWh = \(\frac{\text { watt } \times \text { hour }}{1,000}\)
or
Energy in KWh = \(\frac{\text { volt } \times \text { ampere } \times \text { hour }}{1,000}\)

Question 18.
Which instrument is used to measure current in the circuit? How is it connected in the circuit?
Answer:
Ammeter is used to measure current in a circuit. It is always connected in a circuit in such a way that total current may flow through it. It is, therefore, connected in series in a circuit. Ammeter has very small resistance and connected in series would not change current in the circuit.

Question 19.
Define unit of electric energy.
Or
Define 1 watt hour.
Answer:
The unit of electric energy is joule or watt second or watt hour.
Definition of watt hour: Electric energy consumed is said to be 1 watt hour when 1 ampare of current flows for 1 hour through a conductor whose ends are maintained at a potential difference of 1 volt.
1 watt hour = 1 watt × 1 hour
= 1 volt × l ampere × 1 hour.
The bigger unit of electric energy is kilowatt hour.
1 kilowatt hour (1 kwh) = 1000 watt hour.

Question 20.
How many joules are present in 1 kilowatt hour?
Or
Define kilowatt hour.
Answer:
Kilowatt-hour: If 1 kilowatt of electric power is used by an agent for 1 hour then the electric energy consumed is 1-kilowatt hour (1 kwh).
1 kwh = 1 kw × l h
= 1000 w × 3600 s
= 1000 \(\frac{j}{s}\) × 3600 s
1 kilowatt hour (1 kwh) = 36 × 10⁵ J.

Question 21.
Why is it that very small amount of heat is produced in connecting wires whereas large amount of heat is produced in heating filament of electric bulbs?
Answer:
The resistane of filament of electric .bulb is very high as compared to that of connecting wires. Therefore, if same amount of current flows through both of them then the filament of the bulb due to its high resistance opposes the flow of current causing heat to be produced while in connecting wires this is just its opposite.

Question 22.
Give reasons for the following :
(a) If you connect ammeter in parallel it burns.
Answer:
The resistance of ammeter is comparatively zero with regard to resistance of other components of the circuit. When ammeter is connected in parallel then the total potential difference of the circuit applies between the terminals of the ammeter with the result high current flows through the ammeter. This results in producing large quantity of heat thus burning the ammeter.

(b) Resistivity of some materials if decreases suddenly to zero below a certain temperature.
Answer:
When the temperature of a conductor becomes less than the critical temperature then the material becomes super conductor and its resistances immediately reduces to zero.

Question 23.
What is the effect on resistance, if:
(а) The length of wire is increased
Answer:
Resistance is directly proportional to the length of wire. Therefore, on increasing length of wire, its resistance gets increased.

(b) The area of cross section is increased.
Answer:
Resistance of conductor is inversely proportional to the area of cross-section. In other words, resistance of thick wire (having more area of cross-section) is less than a thin wire. Therefore, if the area of cross-section is increased than its resistance further decreases.

Numerical Problems

Question 1.
Current of 100 mA flows through the filament of an electric hulb for 30 minutes. Calculate the charge that flows through the circuit.
Answer:
Given : Current, I = 100 mA
= 0.1 A
Time, t = 30 min = 30 × 60 s
1800 s

∴ Charge flowing through the circuit, Q = I × t
= 0.1 A × 1800 s
= 180 C

Question 2.
60 coulomb of charge flows through a circuit for 5 minutes. Calculate the current flowing in a circuit.
Answer:
Given : Time, t = 5 min
= 5 × 60 s
Charge, Q = 60 C
Current flowing in the circuit, I =?
We know, current, I = \(\frac{\text { Charge (Q) }}{\text { Time }(t)}\)
= \(\frac{60 \mathrm{C}}{300 \mathrm{~s}}\)
= \(\frac{1}{5}\) A
= 0.2 A

Question 3.
Calculate the area of cross-section of wire vrhose length is 1.0 m and resistance is 23 Ω. Take specific resistance of the material of wire as 1.84 × 10^-6 ohm-m.
Answer:
Given : Length of wire (l) = 1.0 m
Resistance of wire, (R) = 23 Ω
Specific resistance of wire (ρ) = 1.84 × 10^-6 Ω m
Area of cross-section of wire (A) =?
Using R = ρ × \(\frac{l}{A}\)
23 = 1.84 × 10^-6 × \(\frac{l}{A}\)
or
A = \(\frac{1.84 \times 10^{-6} \times 1}{23}\)
A = 8 × 10^-8 m²

Question 4.
Resistance of a metal wire of length 1 m is 26 Ω at 20°C. If the diameter of the wire is 0.3 mm, what will be the resistivity of the metal at that temperature? Using standard table of resistivity of various metals, predict the material of the wire.
Answer:
Given : Resistance of the wire (R) = 26 Ω
Diameter of the wire (d) = 0.3 mm
= 3 × 10^-4 m
Length of the wire (l) = 1 m
∴ Resistivity of the wire (ρ) = \(\frac{RA}{l}\)

= 1.84 × 10^-6 Q m

Question 5.
From the given labeled circuit diagram, find :
(a) Resultant resistance of the circuit
(b) Current flowing in the circuit.

Answer:
(a) Suppose R’ is the equivalent resistance of the parallel arrangement of resistors 3Ω, 3Ω and 3Ω between points B and C, then ;
\(\frac{1}{\mathrm{R}^{\prime}}=\frac{1}{3}+\frac{1}{3}+\frac{1}{3}\)
= \(\frac{1+1+1}{3}\)
= \(\frac{3}{3}\)
∴ R’ = 1 Ω
Let R be the total resistance of series combination of 4 Ω between A and B and R’ = 1 Ω between B and C, then
R = 4Ω + R’
= 4 Ω + 1 Ω
∴ R = 5 Ω
Therefore, resultant resistance of the circuit is 5 Ω

(b) Now, potential difference of the battery (V) = 6V
and total resistance of the circuit (R) = 5 Ω
Current flowing in the circuit (I) = \(\frac{\mathrm{V}}{\mathrm{R}}\)
I = \(\frac{6 \mathrm{~V}}{5 \Omega}\)
I = 1.2 A

Question 6.
(a) In an electric circuit, a battery of five cells each of 2V, resistors of 5 Ω, 10 Ω and 15 Ω and a key plug are connected in series arrangement. Draw its schematic diagram.
Answer:
Schematic Diagram of the Circuit

(b) Calculate the value of current flowing in this circuit when plug is introduced in the key.
Answer:
Three resistors of 5Ω, 10Ω and 15Ω when formed in series have resultant resistance R, then ;
R = R₁ + R₂ + R₃
= 5 Ω + 10 Ω + 15 Ω
= 30 Ω
According to ohms law, I = \(\frac{\mathrm{V}}{\mathrm{R}}\)
I = \(\frac{10 \mathrm{~V}}{30 \Omega}\)
I = \(\frac{1}{3}\)A

Question 7.
An electric lamp, whose resistance is 20 Ω and a conductor of 4 Ω resistance are connected to a 6 V battery as shown in the figure. Calculate (a) total resistance of the circuit (6) the current through the circuit (c) the P.D. across the electric lamp and conductor.
Answer:
Given : Resistance of lamp R₁ = 20 Ω
and Resistance of conductor R₂ = 4 Ω
Pot. difference of battery V = 6V
(a) ∵ both the resistances are connected in series,
∴ Total resistance of the circuit R = R₁ + R₂
= 20 Ω + 4 Ω
= 24 Ω

(b) Total potential difference in the circuit V = 6 V
Total resistance in the circuit, R = 24 Ω
∴ Total current in the circuit, I = \(\frac{\mathrm{V}}{\mathrm{R}}\)
I = \(\frac{6 \mathrm{~V}}{24 \Omega}\)
I = 0.25 A

(c) Pot, difference across the lamp. V₁ = 20 Ω × 0.25 A
V₁ = 5V
and Pot, difference across the conductor, V₂ = 4 Ω × 0.25 A
V₂ = 1V

Question 8.
98 J of heat is produced each second in 2 resistor. Find the potential difference.
Answer:
Here, H = 98 J
R = 2Ω
t = Is
Potential difference, V = ?
Using H = I²Rt
98J = I² × 2Ω × 1s
or I² = \(\frac{98}{2 \times 1}\)
I = \(\sqrt{49}\)
=7A
∴ 1= 7A

Thus, potential difference across the resistor,
V = I × R
V = 7A × 2 Ω
V = 14 volt.

Question 9.
The rating of an electric heater is 1100 W; 220V. Calculate the resistance when it operates at 220 V. Also calculate the energy consumed in kWh in the month of November, if the heater is used daily for 4 hours at the rated voltage.
Answer:
Here P = 1100 W
V = 220 V
R =?
Number of days = 30
t = 4h × 30

Energy consumed by the heater in the month of November,
E = P × t
= 1100 W × (4 × 30 h)
= 132000 Wh
= 132 kWh

Question 10.
What is the (a) highest (b) lowest resistance that can be secured by combination of four Coils of resistance 4Ω, 8Ω, 10Ω and 20Ω?
Answer:
(a) For highest resistance, resistors are connected in series :
R = R₁ + R₂ + R₃ + R₄
= 4Ω + 8Ω + 10Ω + 20 Ω = 42 Ω

(b) The lowest resistance will be obtained when these are connected in parallel.

Question 11.
An electric bulb of power 40 W is lighted daily for 8 hours for 15 days. How many units of electric energy will be consumed? Also find the amount of electric bill if the rate of electricity consumption is ₹ 8.00 per unit.
Answer:
Given : Power, P = 40 W
Time each day = 8 hrs
No. of days = 15 days
∴ Total time for which bulb is lighted, t = 8 × 15 h
Now, electric energy consumed E = P × t
= 40 W × (8 × 15 h)
= 4800 Wh

∴ Electric energy consumed in units = \(\frac{4800}{1000}\)
= 4.8kWh
= 4.8 units

Amount of electric bill = No. of units × Rate
= 4.8 × 8.00
= ₹ 38.40

Question 12.
A household uses the following electric appliances :
(а) The refrigerator of rating 400 W for 10 hours each day
(b) Two electric fans of rating 80 W each for 12 hours each day
(c) Six electric tubes of rating 18 W each for 6 hours each day! Calculate the electricity bill of the household for the month of April if the cost per unit of electric energy is ₹ 4.00
Answer:
Electric energy consumed by all appliances working together each day = (400 × 10) + (2 × 80 × 12) + 6 × 18 × 6
= 4000 Wh + 1920 Wh + 648 Wh = 6568 Wh
= 6.568 kWh (units)
Total electric energy consumed in 30 days of April = 6.568 × 30 units
= 65.68 × 3
= 197.04

Electric Bill = 197.04 × 4
= ₹ 788.16

Question 13.
An electric motor takes 5 A current from 220 V line. Determine the power of the motor and energy consumed in 2 hours.
Answer:
Given, V = 220 volt ; I = 5 A ; t = 2 hour = 7,200 s
Power consumed VI = 220 V × 5 A
= 1,100 watts
Vlt = 220V × 5 A × 2 h
= 2,200 Wh
= 2.2 kWh
or Energy consumed in S.I units = 1100 × 5 × 7200 s
= 3.96 × 107 J

Very Short Answer Type Questions

Question 1.
Define energy.
Answer:
Energy. It is the capacity to do work.

Question 2.
Define electric energy.
Answer:
Electric Energy. Work done is the electric energy used to produce heat energy in an electric circuit.

Question 3.
Define electric current and state its unit.
Answer:
Current. It is rate of flow of electric charge. Its unit is ampere.

Question 4.
Define a volt, whose unit is this?
Or
What is P.D.? Give SI unit.
Answer:
P.D. (Volt) is work done in moving 1 coulomb of + ve charge from one point to other. It is the unit of potential difference. SI unit of P.D. is JC^-1 or volt.

Question 5.
Show the switch signs in circuit in (i) open (ii) closed circuit.
Answer:
Circuit Sign

Question 6.
Is electric potential a scalar or a vector quantity?
Answer:
It is a scalar quantity.

Question 7.
What is practical unit of power and electric energy?
Answer:
Practical unit of power is watt and that of electric energy is kWh (kilo watt hour).

Question 8.
Which one is having more resistance, 100 W bulb or a 50 W bulb?
Answer:
Resistance of 50 W bulb is twice that of 100 W bulb.

Question 9.
What constitutes the current?
Answer:
Flow of free electrons constitute the current.

Question 10.
What is SI unit of resistivity?
Answer:
It is ohm-m.

Question 11.
What is conductor of electricity? Give two examples.
Answer:
Conductor of electricity. A substance that allows the electric current to pass through it is called conductor of electricity.

Examples :

• Copper
• Silver
• Human body.

Multiple Choice Questions:

Question 1.
V ∝ I law was given by:
(A) Faraday
(B) Watt
(C) Ohm
(D) Coulomb.
Answer:
(C) Ohm

Question 2.
The unit of Potential is:
(A) Ampere
(B) Volt
(C) Ohm
(D) Watt.
Answer:
(B) Volt

Question 3.
The unit of electric energy is:
(A) Ampere
(B) Volt
(C) Ohm
(D) Watt
Answer:
(D) Watt

Question 4.
Resistance of a conductor depends on:
(A) its length
(B) its area of cross section
(C) nature of its material
(D) All of these.
Answer:
(D) All of these.

Question 5.
What maximum resistance can be obtained by combining three resistances each of ___________
(A) \(\frac{1}{3}\) Ω
(B) 1Ω
(C) \(\frac{1}{9}\) Ω
(D) 3Ω.
Answer:
(B) 1Ω

Question 6.
By which unit electric current is represented?
(A) Coulomb
(B) Ampere
(C) Watt
(D) Kilowatt.
Answer:
(B) Ampere

Question 7.
Electric current in circuits is measured by:
(A) Ammeter
(B) Voltmeter
(C) Galvanometer
(D) Electric meter.
Answer:
(A) Ammeter

Question 8.
How is Ammeter always connected in circuits? :
(A) in series
(B) in parallel
(C) both in series and parallel
(D) None of these.
Answer:
(A) in series

Question 9.
How is potential difference between two points expressed?
(A) V = \(\frac{\mathrm{W}}{\mathrm{Q}}\)
(B) Q = VW
(C) W = \(\frac{\mathrm{V}}{\mathrm{Q}}\)
(D) V = \(\frac{\mathrm{Q}}{\mathrm{W}}\)
Answer:
(A) V = \(\frac{\mathrm{W}}{\mathrm{Q}}\)

Question 10.
How much work is done to carry 2 C of charge between two points?
(A) 2 J
(B) 6 J
(C) 24 J
(D) J.
Answer:
(C) 24 J

Question 11.
According to ohm’s law:
(A) R = \(\frac{\mathrm{I}}{\mathrm{V}}\)
(B) R = \(\frac{\mathrm{V}}{\mathrm{I}}\)
(C) V = \(\frac{\mathrm{R}}{\mathrm{I}}\)
(D) I = \(\frac{\mathrm{V}}{\mathrm{R}}\)
Answer:
(B) R = \(\frac{\mathrm{V}}{\mathrm{I}}\)

Fill in the blanks:

Question 1.
A stream of ________ moving through a conductor constitutes, electric current.
Answer:
electrons.

Question 2.
The SI unit of electric current is ________
Answer:
Ampere.

Question 3.
In an electric circuit ________ is always connected in parallel.
Answer:
Voltmeter.

Question 4.
The equivalent resistance of number of resistors will be lesser, if they are connected in ________
Answer:
parallel.

Question 5.
If the potential difference across the ends of a conductor is 1 volt and the current flowing through the conductor is 1 Ampere, then the resistance of the conductor is ________
Answer:
1 Ω.

Punjab State Board PSEB 10th Class Hindi Book Solutions Chapter 11.i माँ का कमरा Textbook Exercise Questions and Answers.

PSEB Solutions for Class 10 Hindi Chapter 11.i माँ का कमरा

Hindi Guide for Class 10 PSEB माँ का कमरा Textbook Questions and Answers

(क) विषय-बोध

I. निम्नलिखित प्रश्नों के उत्तर एक या दो पंक्तियों में दीजिये

प्रश्न 1.
बुजुर्ग बसंती कहाँ रह रही थी?
उत्तर:
बसंती अपने पुश्तैनी घर में रह रही थी।

प्रश्न 2.
बुजुर्ग बसंती को किस का पत्र मिला?
उत्तर:
बुजुर्ग बसंती को नगर में उच्च पद पर नौकरी करने वाले अपने पुत्र का पत्र मिला था।

प्रश्न 3.
बसंती की पड़ोसन कौन थी?
उत्तर:
बसंती की पड़ोसन रेशमा थी।

प्रश्न 4.
बसंती बेटे के साथ कहाँ आई थी?
उत्तर:
बसंती नगर में अपने पुत्र के घर आई थी।

प्रश्न 5.
कोठी में कितने कमरे थे?
उत्तर:
कोठी में तीन बैडरूम, एक ड्राईंग रूम और नौकरों के कमरे थे।

प्रश्न 6.
नौकर ने बसंती का सामान कहाँ रखा था?
उत्तर:
नौकर ने सामान बरामदे के साथ वाले कमरे में रखा था।

II. निम्नलिखित प्रश्नों के उत्तर तीन-चार पंक्तियों में दीजिये

प्रश्न 1.
बेटे ने पत्र में अपनी माँ बसंती को क्या लिखा?
उत्तर:
बेटे ने अपनी माँ को लिखे पत्र में लिखा था कि उसकी तरक्की हो गई है। उसे उसकी कंपनी ने रहने के लिए बहुत बड़ी कोठी दे दी है। वह अब रहने के लिए उसके पास शहर में आ जाए। उसे किसी तरह की कोई तकलीफ़ नहीं होगी।

प्रश्न 2.
पड़ोसन रेशमा ने बसंती को क्या समझाया?
उत्तर:
पड़ोसन रेशमा ने बसंती को समझाया था कि उसे बेटे के पास रहने के लिए नहीं जाना चाहिए। शहर में रहने वाले बहू-बेटे बड़े-बुजुर्गों को अपने पास रहने के लिए बुला तो लेते हैं पर उन्हें सम्मान से रखते नहीं। वे उनसे नौकरों वाले काम करवाते हैं। उन्हें ठीक तरह से खाने-पीने को भी नहीं देते। बुजुर्गों का जीवन तो कुत्तों के जीवन से भी बदतर हो जाता है।

प्रश्न 3.
बसंती क्या सोचकर बेटे के साथ शहर आई?
उत्तर:
बसंती को अपने पुत्र पर भरोसा था। फिर भी पड़ोसन के डराने से वह मन ही मन भयभीत थी। अगले दिन जब बेटा इसे ले जाने के लिए स्वयं कार ले कर आ गया तो वह उसकी ज़िद के कारण शहर जाने के लिए तैयार हो गई। उसने सोच लिया था कि ‘जो होगा देखा जावेगा।

प्रश्न 4.
बसंती के कमरे में कौन-कौन सा सामान था?
उत्तर:
बसंती को अपना कमरा तो स्वर्ग जैसा सुंदर लगा था। उसमें डबल-बैड बिछा हुआ था। टी०वी० पड़ा था। एक टेपरिकार्डर भी था। दो कुर्सियां पड़ी थीं। बैड पर बहुत नर्म गद्दे थे।

प्रश्न 5.
बसंती की आँखों में आँसू क्यों आ गए?
उत्तर:
बसंती की आँखों में खुशी के आँसू आ गए थे। उसे ऐसी संपन्नता भरा जीवन अब तक कभी नहीं प्राप्त हुआ था। वह अपने पुश्तैनी-पुराने घर में जैसे-तैसे अकेली जीवन काट रही थी। अब वह अपने बेटे और परिवार के साथ सुख पूर्वक रह सकेगी। उसका बुढ़ापा आराम से कट जाएगा। उसके पुत्र ने आज के कुछ स्वार्थी पुत्रों जैसा व्यवहार नहीं किया था।

प्रश्न 6.
‘माँ का कमरा’ कहानी का उद्देश्य क्या है ?
उत्तर:
‘माँ का कमरा’ एक सोद्देश्य पूर्ण लघु कथा है। आज के स्वार्थ भरे समय में नई पीढ़ी के अनेक पुत्र बुजुर्ग माता-पिता को अपने पास बुला कर उनसे नौकरों की तरह काम करवाते हैं। बूढ़े माँ-बाप का जीवन नरक-सा बन जाता है लेकिन अभी भी अनेक ऐसे युवक हैं जो अपने माता-पिता का सम्मान करते हैं। उनके प्रति अपनत्व का भाव रखते हैं। वे समझते हैं कि जैसे उनके बचपन में माता-पिता ने उन्हें अपना सब कुछ लगाकर बड़ा किया; पढ़ाया-लिखाया था उसी प्रकार अब उन्हें भी बूढ़े हो चुके माता-पिता की सेवा करनी चाहिए। उनके बुढ़ापे का सहारा बनना चाहिए। लेखक ने लघुकथा के माध्यम से बहुत बड़ा संदेश दिया है।

(ख) भाषा-बोध

I. निम्नलिखित पंजाबी गद्यांश का हिंदी में अनुवाद कीजिए

ਛੋਟੇ ਜਿਹੇ ਪੂਸ਼ਤੈਨੀ ਮਕਾਨ ਵਿੱਚ ਰਹਿ ਰਹੀ ਬਜ਼ੁਰਗ ਬਸੰਤੀ ਨੂੰ ਦੂਰ ਸ਼ਹਿਰ ਰਹਿ ਰਹੇ ਪੁੱਤਰ ਦਾ ਪੱਤਰ ਮਿਲਿਆ‘ਮਾਂ ਮੇਰੀ ਤਰੱਕੀ ਹੋ ਗਈ ਹੈ। ਕੰਪਨੀ ਵੱਲੋਂ ਮੈਨੂੰ ਰਹਿਣ ਨੂੰ ਬਹੁਤ ਵੱਡੀ ਕੋਠੀ ਮਿਲੀ ਹੈ, ਹੁਣ ਤਾਂ ਤੈਨੂੰ ਮੇਰੇ ਕੋਲ ਸ਼ਹਿਰ ਵਿੱਚ ਆ ਕੇ ਰਹਿਣਾ ਹੀ ਪਵੇਗਾ।
उत्तर:
अनुवाद-छोटे से पुश्तैनी मकान में रह रही बुजुर्ग बसंती को दूर शहर रह रहे बेटे का पत्र मिला-“माँ मेरी तरक्की हो गई है। कंपनी की ओर से मुझे रहने के लिए बहुत बड़ी कोठी मिली है, अब तो तुम्हें मेरे पास शहर में आकर रहना ही होगा।”

(ग) रचनात्मक अभिव्यक्ति

प्रश्न 1.
आप अपने घर या आस पड़ोस में बुजुर्गों की बेहतरी के लिए क्या-क्या करेंगे?
उत्तर:
हमें अपने घर या आस-पड़ोस में बुजुर्गों की बेहतरी के लिए काम करने चाहिए। हम उनके कहने पर उन्हें बाज़ार से घर का आवश्यक सामान लाकर देंगे। समय-समय पर उनके घर जाकर पूछेगे कि उन्हें किसी चीज़ की आवश्यकता तो नहीं। यदि आवश्यकता होगी तो उसे हम बाज़ार से लाकर देंगे। शाम के समय उन्हें पार्क में सैर के लिए ले जाएंगे। यदि वे घर में अकेले रहते हैं तो इन से बातें करेंगे। यदि वे चाहेंगे तो उनके साथ कैरम आदि खेलेंगे। आवश्यक होने पर उन्हें डॉक्टर के पास लेकर जाएंगे।

प्रश्न 2.
आप घर में अपनी माँ की मदद किस प्रकार करते हैं? कक्षा में चर्चा कीजिए।
उत्तर:
अपने अध्यापक की सहायता से कक्षा में सब मिलकर चर्चा कीजिए।

(घ) पाठ्येतर सक्रियता

प्रश्न 1.
पत्र-पत्रिकाओं में छपने वाली लघुकथाएं पढ़िए।
उत्तर:
स्वयं कीजिए।

प्रश्न 2.
विद्यालय की वार्षिक पत्रिका में लघुकथा लिखने का प्रयास कीजिए।
उत्तर:
स्वयं कीजिए।

प्रश्न 3.
‘माँ’ पर कविताओं का संकलन कीजिए।
उत्तर:
स्वयं कीजिए।

(ङ) ज्ञान-विस्तार

‘माँ का कमरा’ लघुकथा हमें सदा अच्छा सोचने की प्रेरणा देती है। हमें किसी के बारे में सदा गलत नहीं सोचना चाहिए क्योंकि यदि हम दूसरों के विषय में सदा यही सोचते रहें कि वह अच्छा नहीं है, उसमें बुराइयाँ ही बुराइयाँ हैं तो हमें कुछ भी अच्छा नहीं लगेगा, इसलिए कहा गया है कि-
बुरा जो देखन मैं चला बुरा न मिला कोई।
जो मन देखा अपना मुझसा बुरा न कोई॥
इसलिए सदा अच्छा सोचो, अच्छा देखो, अच्छा करो इसी से अपना तथा समाज का भला है।

PSEB 10th Class Hindi Guide माँ का कमरा Important Questions and Answers

प्रश्न 1.
बसंती का बेटा अपने पुश्तैनी घर से दूर क्यों रहता था?
उत्तर:
बसंती का बेटा शहर में कहीं नौकरी करता था इसलिए वह अपने पुश्तैनी घर से दूर रहता था।

प्रश्न 2.
पुत्र को कंपनी ने क्या दिया था?
उत्तर:
पुत्र को कंपनी ने रहने के लिए बहुत बड़ी कोठी दी थी।

प्रश्न 3.
बसंती की पड़ोसन ने किस महिला के पछताने की बात कही थी? क्यों?
उत्तर:
बसंती की पड़ोसन ने बचनी नामक महिला के पछताने की बात कही थी। उसे शहर में रहने के लिए बहूबेटे ने अपने पास बुला लिया था और नौकरानी की तरह उससे व्यवहार किया था। वे उसे न वक्त पर रोटी देते थे और न ही चाय। उसका जीवन तो कुत्ते से बुरा हो गया था।

प्रश्न 4.
बसंती शहर में किस तरह गई थी?
उत्तर:
बसंती का बेटा शहर से आया था और उसे अपनी कार में बिठा कर ले गया था।

प्रश्न 5.
बसंती का बेटा माँ को घर छोड़ कर कहाँ चला गया था?
उत्तर:
बसंती का बेटा माँ को घर छोड़ कर अपने किसी ज़रूरी काम को पूरा करने के लिए चला गया था।

प्रश्न 6.
बसंती की बहू और बच्चे घर क्यों नहीं थे?
उत्तर:
बसंती की बहू अपने काम पर चली गई थी और बच्चे स्कूल में पढ़ने के लिए गए हुए थे।

प्रश्न 7.
कोठी के तीन कमरों के बारे में बसंती ने क्या सोचा था?
उत्तर:
कोठी के तीन कमरों के बारे में बसंती ने सोचा था कि एक कमरा बहू-बेटे का होगा, दूसरा बच्चों का और तीसरा मेहमानों के लिए होगा।

प्रश्न 8.
पिछवाड़े में नौकरों के लिए बने कमरे कैसे थे?
उत्तर:
पिछवाड़े में नौकरों के लिए बने कमरे छोटे थे पर वे रहने योग्य अवश्य थे।

प्रश्न 9.
माँ क्या सोचकर बिस्तर से उठ बैठी थी?
उत्तर:
माँ यह सोचकर बिस्तर से उठ बैठी थी कि वापस आकर उसका बेटा कहीं उसे डाँटे नहीं कि वह उन नर्म गद्दों पर लेट क्यों गई थी।

प्रश्न 10.
बसंती किस बात को सुनकर आश्चर्यचकित रह गई थी?
उत्तर:
बसंती इस बात को सुनकर आश्चर्यचकित रह गई थी कि घर के तीन बड़े कमरों में से एक कमरा उसका था जिसमें डबल-बैड लगा हुआ था।

माँ का कमरा कठिन शब्दों के अर्थ

पुश्तैनी = जो कई पीड़ियों से चला आ रहा हो। बुजुर्ग = बड़ी आयु वाले। जून = जन्म (योनी)। तरक्की = उन्नति। तकलीफ = परेशानी; कष्ट। दुर्गति = बुरी दशा। वक्त = समय। सफर = यात्रा। पिछवाड़े = पिछला हिस्सा। टिका दिया = रख दिया। देख-रेख = निगरानी। आश्चर्यचकित = हैरान। पुनः = दुबारा । बेझिझक = बिना किसी झिझक के। आलिंगन = गले लगाया। सुखद = सुख देने वाला।

माँ का कमरा Summary

माँ का कमरा लेखक परिचय

जीवन परिचय- श्री श्याम सुंदर अग्रवाल पंजाब के प्रतिष्ठित लघुकथाकार हैं। इनका जन्म पंजाब राज्य के कोटकपूरा में 8 फरवरी, सन् 1950 ई० में हुआ था। बी०ए० तक की शिक्षा प्राप्त करने के पश्चात् ये लोक निर्माण विभाग में कार्यरत रहे। सन् 1988 ई० में इन्होंने पंजाबी पत्रिका ‘पिन्नी’ का संपादन कार्य आरंभ किया। यह पत्रिका त्रैमासिक है। अपनी नौकरी के दौरान ही इन्होंने हिंदी और पंजाबी में लघुकथा लेखन का कार्य आरंभ किया था। ये बाल-साहित्य की रचना भी करते हैं।

रचनाएँ-श्री अग्रवाल के फुटकर लघु कथनाओं के अतिरिक्त दो लघुकथा संग्रह अब तक प्रकाशित हुए हैं। उनके नाम हैं-‘नंगे लोका दा फिक्र’, ‘मारुथल दे वासी’।

साहित्यिक विशेषताएँ-श्री अग्रवाल वर्तमान युग की उस त्रासदी को अभिव्यक्त करने वाले कहानीकार हैं जिन्होंने युग बोध की सार्थकता को व्यक्त करने में सफलता प्राप्त की है। हर वस्तु के दो पक्ष होते हैं-अच्छा और बुरा। बुरा डराता है तो अच्छा मन में सद्भावों को उत्पन्न करता है। लेखक सद्भावों को जगाने में सक्षम है। वह दूर की गोटियां न उठा कर निकट से ही विषय को उठाते हैं। लेखक की भाषा सरल और सहज है। उसमें स्वाभाविकता है। गतिशीलता उसमें विद्यमान है।

माँ का कमरा कहानी का सार

बसंती अपने छोटे-से पुश्तैनी मकान में अकेली रहती थी। उसका पुत्र दूर शहर में नौकरी करता था। उसकी तरक्की हो गई थी। उसने अपनी माँ को शहर में आकर उसके साथ रहने के लिए पत्र लिखा। जब उसकी पड़ोसन को पता लगा तो उसने सलाह दी कि वह ऐसा बिल्कुल न करे। शहरों में प्राय: बहू-बेटे अपने बुजुर्ग माँ-बाप से नौकरों वाले काम कराने के लिए ही उन्हें अपने पास बुलाते हैं। वहाँ जाकर रहना तो कुत्तों से भी बुरी हालत में रहने के बराबर होता है। माँ चिंता में डूबी हुई थी।

उसका पुत्र अपनी कार में उसे लेने आ गया था। ‘जो होगा देखा जायेगा’ – सोचकर माँ पुत्र के साथ चली गई। लंबे सफर के बाद जब माँ वहाँ पहुँची तो उसने देखा कि घर बहुत बड़ा था। तीन कमरों में डबल बैड, एक बढ़िया सजा हुआ कमरा और पीछे नौकरों के कमरे। नौकर एक कमरे में उस का समान रख गया। घर में न तो दोनों बच्चे थे और न बहू। शाम को उसका बेटा वापस घर आया तो माँ ने उससे कहा कि उस का सामान भी उसके कमरे में रखवा देता। बेटे ने बताया कि उसका सामान उसी के कमरे में ही तो था। माँ के लिए ऐसा सुनना हैरान कर गया था। उसने झट उसे गले लगा लिया। खुशी से उसकी आँखें भर आयी थीं।

Punjab State Board PSEB 10th Class English Book Solutions English Grammar Prepositions Exercise Questions and Answers, Notes.

PSEB 10th Class English Grammar Prepositions

Fill in the blanks with suitable Prepositions :

(A) The dowry system degenerated (1) ……… an evil custom. It became necessary (2) ……… the parents (3)……… girls to give a good dowry ……… (4) their daughters. The married life (5) ……… a girl depended (6) ……… the size (7)…….. the dowry. A successful and happy married life became impossible (8)…….. the absence (9)…….. a handsome dowry. Newspapers are full (10) reports carrying tales (11)……..brides being burnt (12) …….. death or driven (13) …….. hang themselves because (14) …….. constant nagging by their in-laws.
Answer:
1. into, 2. for, 3. of, 4. to, 5. of, 6. on, 7. of, 8. in, 9. of, 10. of, 11. of, 12. to, 13. to, 14. of.

(B) Cricket is a game known …….. (1) its wonderful glories. It is, popular (2) …….. men and women (3) …….. all ages. People used to go to see a cricket test match (4) …….. thousands. They used to see a match (5)…….. five days. Many a time, the match would end (6) …….. a draw. But things have changed (7) …….. the introduction (8) ……..one-day matches. This kind …….. (9) cricket has certainly caught the fancy …….. (10) the people. There is no need to wait ……..(11) five days now (12)…….. the outcome (13)…….. the match. A match is now decided (14) …….. the same day.
Answer:
1. for, 2. among, 3. of, 4. in, 5. for, 6. in, 7. with, 8. of, 9. of, 10. of, 11. for, 12. for, 13. of, 14. on.

(C) In modern times, books are being published (1) …….. very large numbers (2) …….. all subjects under the sun. It is not possible (3) ……..a man to read all (4) …….. them. Reading gives us a lot (5) …….. pleasure. Books delight and educate (6) …….. the same time. The Gita gives us a message (7) …….. universal brotherhood. It tells us that a man should go on doing his duty without worrying (8)…….. the results.
Answer:
1. in, 2. on, 3. for, 4. of, 5. of, 6. at, 7. of, 8. about.

(D) It is (1) …….. the very nature (2) …….. adversity to bring out the best (3) …….. man, develop his latent abilities and lead him (4) …….. a path (5)…….. prosperity and progress. The history (6) …….. the world is the story (7)…….. the survival (8) …….. the fittest. In the course of time,man, through his heroic struggle against the adverse circumstances, came out (9) …….. the forest, changed the face (10) the universe and landed (11) …….. the moon.
Answer:
1. in, 2. of, 3. in, 4. to, 5. of,6. of, 7. of, 8. of, 9. of, 10. of, 11. on.

(E) Mr. Blacksmith is known (1) …….. me. Once we met (2) …….. a garden. (3) …….. there, he took me (4) …….. his apartment. I was astonished to see his capabilities as a journalist. I just had a look (5) …….. his face. He was trying to prove his position. He was really a man (6) …….. letters but unfortunately he was blind (7) ……..one eye. I looked (8) …….. the portrait (9) …….. a lady hanging (10) …….. the wall. I went to take a round (11) …….. his house and I saw a family photograph. Mr. Blacksmith was sitting (12). ……. his wife and son (13) the photograph. After spending some time (14) …….. him, I came back home.
Answer:
1. to, 2. in, 3. From, 4. to, 5. at 6. of, 7. in, 8. at, 9. of, 10. on, 11. of, 12. with, 13. in, 14. with.

(F) Life is not a bed (1) …….. roses but a bed (2) ……..thorns. Those who understand the reality (3)…….. life are winners, not losers. One has to go (4) …….. a lot (5) …….. trials and tribulations (6) …….. taking a right decision or (7) ……. making a right choice. God has given us tremendous power to think and decide. But most (8) …….. us are ignorant (9) …….. our capabilities. We should not underestimate ourselves and move (10) …….. the destination (11) …….. any doubts or fears. This behaviour will lead us (12) …….. greater heights.
Answer:
1. of, 2. of, 3. of, 4. through, 5. of, 6. in 7. for 8. of 9. of 10. towards 11. without 12. to.

(G) Translation is an art. Good translation is the result. (1) …….. practice and patience. It requires skill to translate words and ideas (2)…….. one language (3)……..another. Literal translation (4) …….. a sentence sometimes spoils the spirit (5) …….. the language and sounds funny. Ope should translate words and ideas (6)…….. precision. It is essential to be equally well-versed (7) …….. both the languages.
Answer:
1. of 2. of 3. into 4. of 5. of 6. with 7. in.

(H) Positive thoughts are the wings (1) …….. success. One should always look (2) …….. the positive side (3) …….. life. We should not let negative thoughts come (4) …….. our mind, Everybody should have this approach (5) …….. life. Always hope (6)…….. the best and believe (7) …….. God. He is always there to take care (8) …….. His children. God is too great to ask (9) …….. the price (10) …….. the gifts He has bestowed (11)…….. us.
Answer:
1. of 2. at 3. of 4. into 5. to 6. for 7. in 8. of 9. for 10. of 11. on.

(I) First and foremost (1)……..the blessings of civilization are order and safety. We should not quarrel (2) …….. each other. In disputes (3) …….. man and man, right has taken the place (4) …….. might. Law protects us (5) …….. robbery and violence. Nobody can come and break (6) our house, steal our goods or run off (7) …….. our children. Many of us act (8) …….. thinking. This habit has injured the feelings (9)…….. many and has turned friends (10) …….. enemies.
Answer:
1.of 2. with 3. between 4. of 5. from 6. into 7. with 8. without 9. of 10. into.

(J) Dreams have been the topic (1) …….. discussion (2) …….. men (3) …….. centuries. The fact cannot be denied that dreams are far (4) reality but (5) …….. the same time, they open up (6) …….. us a facet (7)……..our personality (8) …….. which we did not know earlier. Dreams take us (9) a world which is more like a Utopia. Some people are (10) …….. the habit (11) …….. daydreaming. They find themselves lost (12) …….. dreams most (13) …….. the time. One must not blind oneself (14) …….. the reality.
Answer:
1. of 2. with 3. for 4. from 5. at 6. before 7. of 8. of 9. into 10. in 11. of 12. in 13. of 14. from.

ऐसे शब्द को Preposition कहा जाता है जो स्थान (place), दिशा (direction), साधन (source), विधि (method), आदि का बोध कराने के लिए किसी Noun अथवा Pronoun से पहले लगाया गया हो; जैसे. In the room; towards the city; through the forest; by all means; into the well; beside me; between us, आदि

The Use Of Some Prepositions

(1) At का प्रयोग छोटे नगरों तथा गांवों के नामों के साथ किया जाता है।
In का प्रयोग बड़े नगरों, प्रान्तों और देशों के नामों के साथ किया जाता है।

1. Mohan lives at Kathua.
2. She was born at Batote.
3. The last Olympic Games were held in Beijing.
4. There are many film studios in Mumbai.

(2) On का प्रयोग तिथियों तथा दिनों के नामों के साथ किया जाता है।
In का प्रयोग महीनों तथा वर्षों के लिए किया जाता है।
At का प्रयोग Point of Time के लिए किया जाता है।

1. I shall go to Delhi on Sunday.
2. Our examination begins on 24th July.
3. Rains started in July.
4. His grandfather died in 2005.
5. We had tea at 5 o’clock.
6. He came at the right time.

(3) In और At के निम्नलिखित समय-सम्बन्धी प्रयोग याद रखिए
In the morning At noon
In the evening At night
In the afternoon At dawn

(4) Between का प्रयोग दो व्यक्तियों । स्थानों । वस्तुओं / आदि के लिए किया जाता है।
Among का प्रयोग दो से अधिक व्यक्तियों । स्थानों । वस्तुओं / आदि के लिए किया जाता है।
1. The two brothers quarrelled between themselves.
2. The three brothers quarrelled among themselves.

(5) In स्थिरता (rest) को प्रकट करता है। ..
Into अन्दर की ओर गति (motion) को प्रकट करता है।
1. He was sitting in the room.
2. The fox fell into the well.

(6) On स्थिरता (rest) को प्रकट करता है।
Upon ऊपर की ओर गति (motion) को, प्रकट करता है
1. The book is on the table.
2. The cat jumped upon the table.

(7) With उस यन्त्र (instrument) की ओर संकेत करता है जिसका प्रयोग कोई काम करने के लिए किया
By काम करने वाले (doer) की ओर सकेत करता है
1. He beat his servant with a stick.
2. The book was written by me.

(8) Beside = निकट,असंगत
Besides = के अतिरिक्त
1. She came and sat beside me.
2. Your answer is beside the mark.
3. I have three other pens besides this.

(9) Since तथा For का प्रयोग Perfect Tense के बाद किया जाता है।
from का प्रयोग किसी भी Tense के बाद किय जाता है
Since और From का प्रयोग point of time के लिए किया जाता है।

For का प्रयोग period of time के लिए किया जाता है।
Since का प्रयोग केवल भूतकाल के सम्बन्ध में ही किया जा सकता है।
From और For का प्रयोग किसी भी काल के लिए किया जा सकता है।

1. He has been ill since Monday last.
2. This timetable has been in force since August.
3. He studied English from the age of ten.
4. This timetable will come in force from Monday.
5. I have been ill for five days.

Fill in the blanks with suitable Prepositions :

(A)
1. How did you come ……….. this ring ?
2. He has no taste ……….. music.
3. She is sick ……….. your company.
4. It is ……….. my power to help you.
5. Radha takes ……….. her mother.
6. He is not attending ……….. his lesson.
7. He jumped ……….. the river.
8. He is well known me.
9. He was shocked ……….. his failure.
10. The silly fellow takes delight ……… the sufferings of others.
Answer:
(A) 1. by 2 for 3. of 4. within 5. after 6. to 7. into 8. to 9. at 10. in.

(B)
1. The Minister gave …… the prizes.
2. He is fully qualified …… this job.
3. My office is …… a stone’s throw from my house.
4. He is a fool …… the firs ……the pupils
the value of discipline. ……
6. What is the time …… your watch ?
7. He was accused …… smuggling.
8. He agreed …… my proposal,
9. Remind him …… his promise.
10. He has disposed his scooter.
Answer:
(B) 1, away 2. for 3. at 4. of 5. upon 6. by 7. of 8. to 9. of 10. of

(C)
1. He died …… overwork.
2. He is fond …… books.
3. I prefer tea …… coffee.
4. There is no delight …… teasing others.
5. She is sorry to part…… her friends.
6. Will you stand …… me in trouble ?
7. Let us hope …… the best.
8. Monika is gifted …… a sweet voice.
9. The Principal received the guests …… the gate.
10. I was able to see …… his trick.
Answer:
1. from 2. of 3. to 4. in 5. from 6. by 7. for 8. with 9. at 10. through.

(D)
1. The patient died …… a serious illness.
2. She is very weak …… English.
3. Rajinder is related …… me.
4. The train arrived late …… 30 minutes.
5. Agra is famous ……..its historical buildings.
6. This pen is superior …… that one.
7. She is proud …… her beauty.
8. I caught him …… the ear.
9. She aims …… becoming a good doctor.
10. We go to school …… education.
Answer:
(D) 1. of 2. in 3. to 4.by 5. for 6 to 7. o18. by 9. at 10. for

(E)
1. She is blind …… one eye.
2. She is fond……music.
3. He prefers tea …… coffee but his father likes coffee more …… tea.
4. Ram went…… the room.
5. The pen is …… the table.
6. I had an interview …… the Head master.
7. This book is full…… errors.
8. He is junior …… me.
9. I am in favour …… a change.
10. This book is more interesting …… that one.
Answer:
1. in 2. of 3. to, than 4. into 5. of 6. with 7. of 8. to 9. of 10. than.

(F)
1. He was given a grand party on the eve …… his retirement.
2. He invited me …… tea.
3. His house is situated …… front of the post office.
4. I go to school…… ten.
5. Water …… this well is dirty.
6. We go …… office every day.
7. I shall return …… a month.
8. Rita is standing …… the door.
9. He ran …… the room.
10. I bought the book …… a low price.
Answer:
1. of 2. to 3. in 4. at 5. of 6. to 7. in & at 9. into 10, at.

(G)
1. He worked …… a long time.
2. The cat is sitting …… the table.
3. I returned from Delhi …… a month.
4. He is blind …… his shortcomings.
5. Always hope …… the best.
6. He acceeded …… my request.
7. He deals …… sugar.
8. He is blessed …… a son.
9. I have made …… my deficiency in ……
10. He was accused …… theft.
Answer:
1. for 2. under 3. after 4, to 5. for 6. to 7. in 8. with 9.up 10. of

(H)
1. He died …… his country.
2. The river abounds …… fish.
3. A drowning man catches …… a straw.
4. He is open …… conviction.
5. She has no sympathy …… you.
6. Her activities are beneficial …… society.
7. He is not deaf …… your entreaty.
8. It has been drizzling …… Monday.
9. He is not ashamed this.
10. They travel …… horseback.
Answer:
1. for 2. in / with 3. at 4. to 5. for 6. to 7. to 8. since 9. of 10. on.