## PSEB Solutions for Class 10 Welcome Life Chapter 2 Critical Thinking

Welcome Life Guide for Class 10 PSEB Critical Thinking Textbook Questions and Answers

1. Where is the other part of Punjab located?
(a) Delhi
(c) Pakistan
(d) Rajasthan
(c) Pakistan

2. How many assembly constituencies are there in Punjab?
(a) 116
(b) 21
(c) 13
(d) 117
(d) 117

3. How many parliamentary constituencies (Lok Sabha) are there in Punjab?
(a) 117
(b) 13
(c) 21
(d) 22
(b) 13

4. By what parent did the Greeks know Punjab?
(a) Sapat-Sindhu
(b) Pentapotamia
(d) Sindh
(b) Pentapotamia.

5. Which is the oldest university in the world associated with Punjab?
(a) Punjabi University
(b) Punjab University
(c) Takshila University
(d) Nalanda University
(c) Takshila University

(Questions for worksheet)

Question 1.
Which misconception was Sandeep holding in her mind?
There was a misconception in Sandeep’s mind that products and tonics increase physical strength and athletes perform better in sports. He was preferring to take medicine and products instead of hard work which is wrong.

Question 2.
What advice did the teacher give to her girl students?
The teacher advised her girl students not to keep misconceptions in their minds. Many people use drugs to show their strong body which is wrong. Kids get caught up in the web of social media ads. We need to think carefully before we fall into the trap of these advertisements. Instead of taking these medications, we should focus more on hard work and an indigenous diet. Madam told the girls that we have many examples where many players from ordinary families have gone through hard work and achieved great success.

Question 3.
Which things should be kept in mind while watching print media, electronic and social media?
Companies advertise their products on print media and social media. This type of advertisement is not a part of any TV channel and the name states that it is a company advertisement. So, before we buy them and fall into their trap, we must find out the truth about them. We must rationally think about whether this is possible. If not, we must not buy that product.

Question 4.
How can we get rid of misconceptions?
We must think rationally about anything whether this is right or wrong. We must talk to others and if our views match, we must remove misconceptions and consider the reason behind them.

PSEB Solutions for Class 10 Welcome Life Critical Thinking Important Questions and Answer

Multiple Choice Questions:

1. Which students are unique and successful?
(a) One who values the time.
(b) One who plays games.
(c) One who is busy on social media
(d) None of these
(a) One who values the time.

2. What has removed gender discrimination in society?
(a) Religion
(b) Science and technology
(c) Society
(d) Government
(b) Science and technology

3. Which example tells us about the courage and kindness of females 7
(a) Mai Bhago
(b) Mata Gujri
(c) Rani Laxmi Bai
(d) All of these
(d) All of these

4. Can we see gender discrimination in modern times 7
(a) Yes
(b) No
(c) Don’t know
(d) Can’t say
(a) Yes

5. We should value ………………..
(a) Money
(b) Time
(b) Superstitions
(d) All of these
(b) Time

6. In the present age, we can save time by properly using ……………..
(a) Religion
(b) Social Media
(c) Newspapers
(d) Magazines
(b) Social Media

7. With ……………… we can spend our time well.
(a) Planning
(b) Mobile
(c) T.V.
(d) None of these
(a) Planning

8. In the present age of modem revolutionary changes, the role of …………… has increased.
(а) Religion
(b) Individual means
(c) Means of communication
(d) Government
(c) Means of communication.

9. What do we get with means of communication?
(a) Information
(b) Knowledge
(c) Entertainment
(d) All of these
(d) All of these

10. What is the demerit of means of communication?
(a) An individual becomes habitual
(c) Children deviate from their actual objective
(d) All of these
(d) All of these

Fill in the Blanks:

1. With the right use of …………., we can achieve our goals.
time

2. We get a lot of information with the help of ……………..
means of communication

3 …………………. should not be misused.
social media

4. Discrimination between …………… and …………….. has been going on in society since time immemorial.
boys,
girls

5. We must not follow ………..
assumptions

True / False:

1. We must avoid misconceptions.
True

2. Gender-based discrimination is a perception of modem society.
False

3. Discrimination between boys and girls has been going on since ancient times.
True

4. Many people fall into the trap of media.
True

5. Eating products is essential for sports.
False

Match the Column:

 Column A Column B (a) Discrimination (i) Means of communication (b) Unique (ii) Sapt Sindhu (c) Schedule (iii) Difference (d) Internet (iv) Special (e) Punjab (v) Time Table

 Column A Column B (a) Discrimination (iii) Difference (b) Unique (iv) Special (c) Schedule (v) Time Table (d) Internet (i) Means of communication (e) Punjab (ii) Sapt Sindhu

Question 1.
Is there gen&er based discrimination in society?
Yes, there is gender-based discrimination in society.

Question 2.
What has significantly reduced gender-based discrimination in society?
Science and technology have significantly reduced gender-based discrimination in society.

Question 3.
From which aspects, we can’t see the difference between a boy and a girl?
From the point of view of courage, mental level, hard work, etc.

Question 4.
Give examples of women’s bravery and kindness.
Mai Bhago, Mata Gujri, Rani Laxmi Bai, etc. are examples of women’s bravery and kindness.

Question 5.
Is there any gender-based discrimination in modern times?
Yes, there is gender-based discrimination in modem times.

Question 6.
Which students are unique and successful?
Students who value time are unique and successful.

Question 7.
Why should we value time?
Because once the time is gone, it never comes back.

Question 8.
What happens if time is wasted?
Time will not appreciate us and we will not be able to succeed in life.

Question 9.
Which student is successful in life?
The student who plans the time becomes successful in life.

Question 10.
What is meant by Time Planning?
It means that time should be planned in a way that every minute could be used.

Question 11.
How can we save time?
We can save time by using social media.

Question 12.
What is the advantage of using social media?
Ans.
We can get a lot of information from social media.

Question 13.
The role of what has increased significantly in modem times?
The role of means of communication has increased significantly in modem times.

Question 14.
What is the main purpose of the companies that run the media?
Their main aim is to earn money.

Question 15.
What do means of communication provide us?
They provide us with different types of information.

Question 16.
What is the disadvantage of misusing means of communication?
People adopt wrong habits and deviate from their actual motives.

Question 17.
What vow students must make before using the internet and mobile?
They must take a vow that they will use them only to increase their knowledge.

Question 18.
What is the advantage of properly using the internet and mean? of communication?
Ans.
They increase one’s knowledge and shine an individual’s personality.

Question 19.
Is it necessary to use products and tonics to play games?
No, there is no need to use such things.

Question 20.
How can we master a sport?
By continuous practice, we can master a sport.

Question 1.
What is means by Gender Discrimination?
There are two genders in society-male and female. If any discrimination takes place between them, it is called gender discrimination. In our society, females are greatly discriminated against in comparison to males. For example, there are certain works, about which it is said that they are only for males. Males are physically powerful and they discriminate against females. Females were not given any rights. It is called gender discrimination.

Question 2.
Does gender discrimination exist in present society?
Yes, gender discrimination still exists in society. Its common example can be seen at any workplace where females are less paid in comparison to males. There are very few women in public life. Most of the crimes are associated with females. Although they are given equal rights by the constitution but are unable to get equality in society.

Question 3.
Should we eliminate discrimination between boys and girls?
Yes, this discrimination must be eliminated from society. An ideal society is based on equality and there must be no discrimination in such a society. If we look at the functions given to males and females, we can easily observe that the more difficult works are given to females and great patience is required to complete them. Males are unable to complete such works in a proper way. That’s why discrimination must be eliminated and efforts must be made to bring social equality.

Question 4.
Why should we value time?
It is said that the past does not come back. Once time runs out, no matter how hard you try, it won’t come back. If we value time, we will be able to do all our work on time and in the right way, time will be of the essence and our lives will be successful. So, first of all, it is important that we should save our time. If we take care of our time then surely we will be able to progress in life and achieve our goals. That’s why it is said that time is money and we should not waste it.

Question 5.
“The right use of time is the best use of time.” Explain the statement.
It is rightly said the right use of time is the best use of time. Actually, it is in our hands that how can we use our time. If a person uses his time wisely, gets an education, and makes efforts to do progress, his knowledge and money definitely increase. But if he did not do so, neither knowledge nor money would have gone to him. A student is always asked to create his own timetable and pay equal attention to all the subjects. If he does not set his own timetable and spends time in vain, the time to come will not be right for him. That’s why everyone must use his time wisely to do progress in life.

Question 6.
How can we use social media in a better way?
The importance of social media in our lives has increased a lot these days. Facebook, Instagram, Google, etc. are included in social media. Out of these, Google can be very helpful for us. Every type of information is available on google. No matter what the subject is, Google provides us with information within a second. In addition, when we get tired of working, we can entertain ourselves on Facebook, Instagram, etc. We can find our old friends and reconnect with them. In this way, we can make our life interesting in many ways by using them properly.

Question 7.
What are the benefits of creating a Whatsapp group of students by a school teacher?

• By creating a Whatsapp group, teachers can give homework to students.
• If a student faces any problem while studying, he can ask questions to the teachers.
• Students answer each other’s questions which allow all the students to repeat the lesson.
• Students get close to each other and help, each other during exam times.
• Proper use of group is beneficial for children as they know what to do or not to do at a particular moment.

Question 8.
Can we improve our game by consuming products and tonics?
No, games cannot be improved by consuming products and tonics. It can only increase physical strength for a particular moment. If the body gets used to it, the body can get damaged. The game can only be improved only with hard work and can achieve great success. It is a misconception that games can be improved by consuming products and tonics. We must avoid such misconceptions.

Question 1.
How can we properly use mobile, the internet, and other means of communication?
The role of communication in our lives has immensely increased in present times and we are using it a lot. We should not become habitual of it. Instead, we should properly use it. With the following methods, we can properly use mobile, the internet, and other means of communication :

• We must not play games on mobiles. Instead, we should use it to attain knowledge.
• Every type of information is available on Google. By using means of communication, we must collect information and become efficient in our subject.
• Presently, students are taking education with mobile and internet. It should be used wisely.
• More usage of mobile or computer can have an adverse impact on our eyes. It must be used to a limited extent.
• By using such means, we can develop our personality and can create a better future.
• With their help, students can achieve their goal i.e. progress in life.

Critical Thinking PSEB 10th Class Welcome Life Notes

• For centuries, there has been discrimination between boys and girls in our society. Boys are considered superior to girls and the major reason for this is the male-dominated society.
• In modem times, science and technology have largely eliminated this gender discrimination.’ Although this discrimination is reduced still this discrimination still prevails in many areas.
• We have many examples in history which show that when required, females have shown great courage. This also shows us certain qualities in females such as courage, helping others, etc.
• While living in a society, we must oppose every type of discrimination and try to bring equality in society.
• We must use time wisely and not misuse it. If we do not value time today, tomorrow will not value us.
• It is a must for us to make a timetable and live life according to it. It will bring discipline into our lives and we will be able to do everything at the right time.
• We must use social media in a better way. We must get good knowledge and only devote that much time to social media which is required. For entertainment, we can use other means as well except social media.
• We must use mobile, the internet, and other means of communication in a constructive way. They provide us with very good material to study. By using them in a proper way, we can create a better personality. It is a must for every student to use them in a constructive way.
• There is a lot of negativity spread around us. We must avoid any kind of negativity and must try to adapt and spread positivity.
• At the same time, we must avoid the misconceptions that exist in society. We must use our discretion and mind to avoid misconceptions and try to remove them from society.

Punjab State Board PSEB 10th Class Welcome Life Book Solutions Chapter 2 Critical Thinking Textbook Exercise Questions and Answers.

## PSEB Solutions for Class 12th Class Physical Education  Chapter 2 Sports Training

Physical Education Guide for Class 12 PSEB Sports Training Textbook Questions and Answers

Question 1.
How many types of warming-up are there? Name them.
There are two types of warming up:

• Physiological warming up
• Psychological warming up.

Question 2.
Write any one benefit of Interval training Method.
Since, hardly any training aids are required, more athletes can be trained at the same time.

Question 3.
How is the word Training used in sports?
Sports training is the entire systematic process of preparation of athletes for highest level of performance.

Question 4.
Write the meaning of sports training.
In general, the word sports training is commonly used by the sportsperson in the field of sports. But, in broad sense training may be defined as an organised and systematic instructional process which aims to improve the individual’s physical, psychological and intellectual performance or tactical capabilities.

Question 5.
Write one aim of sports training.
Development of Overall Personality. Overall personality can be observed with habits, self esteem, social skills, behaviour, leadership, abilities, resilience, values, team building etc. towards the requirements of training of competition. These are the personality traits that can be achieved or improved through sports during training. Hence, sports training play an important role in the development of personality.

Question 6.
What do you know about physical structure?
Physical structure means physique body structure or work efficiency. Shape of muscles and structure of bones can be identified through medical procedure. Inspite of these factors hereditary factors also play an important role in games and sports.

Question 7.
Write a note on the following:
(i) Physical fitness
(ii) Technical Expertise
(iii) Technical skills
(iv) Development of overall personality.
(i) Physical Fitness:
It refers as one must possess physical fitness components e.g. strength, speed, endurance, agility, balance, power etc. these components can be achieved through regular physical training and are prerequisites of all sports. These physical fitness components vary from sports to sports e.g. some sports requires strength and endurance and other needs agility etc. With the help of physical training plan e.g. short term and long term plan, plan according to participation in general or specific competitions etc. can be achieved easily.

(ii) Technical Expertise:
Technical skill is a fundamental component of sports training. It refers to improve set of exercises and various skills used in various sports to achieve highly optimum performance or efficiency. Technical skill consists of various repeats (in order to become skill), initial training of athlete, abilities of athlete, motor abilities (fitness components), sensory abilities (understanding level of complex situation) etc. these above said fundaments can be achieved regular practice. For this, technical skill can divide in phases e.g. athlete must be prepared themselves for physical fitness, skill improvement training etc.

(iii) Technical skills:
Technical skill is a fundamental component of sports training. It refers to improve set of exercises and various skills used in various sports to achieve highly optimum performance or efficiency. Technical skill consists of various repeats (in order to become skill), initial training of athlete, abilities of athlete, motor abilities (fitness components), sensory abilities (understanding level of complex situation) etc. these above said fundaments can be achieved regular practice. For this, technical skill can divide in phases e.g. athlete must be prepared themselves for physical fitness, skill improvement training etc.

(iv) Development of overall personality:
Overall personality can be observed with habits, selfesteem, social skills, behaviour, leadership, abilities, resilience, values, team building etc. towards the requirements of training of competition. These are the personality traits that can be achieved or improved through sports during training. Hence, sports training play an important role in the development of personality.

All games and sports certainly benefit both mind and body and create discipline, team building, confidence and physical fitness. Sports training enhance strength, speed, skill, endurance, and flexibility but also increases self esteem, builds social skills and leadership, increases resilience and inculcates values. These specific personality traits which are more suitable to attain high level of sports performance in sports can be develop with the help of sports training.

Question 8.
What is warming up? What is the difference between psychological and Physical warm up? .
“Warming up is a preliminary exercises of physical and mental preparation for a strenuous exertion”.
“Warming up is a process of heating the whole body by running and performing exercises prior to the activity”.
“Warming up is a process by which human machine is brought to a condition at which it safely responds to the nerves impulses of the persons for quick and efficient action”.

1. Physiological warming up:
It is mainly when the light exercises are performed in order to have benefits of muscular contraction due to increase in temperature of the muscles. It can furthur be classified into following two categories:

(i) Active warming up:
It involves bodily movement such as light exercises, jogging etc. to increase body temperature.
It is furthur of two types:
(a) General warming up
(b) Specific warming up

(a) General warming up:
In this type of warm-up athlete does not engage themselves in a specific activity. It generally last from eight to ten minutes. This warm-up might include very easy jogging or vigorous walking, strides and simple exercises which are helpful to increase the heart rate.

(b) Specific warming up:
In this type of warming up athlete must follow specific exercises related to game or activity. For example sprinter must do strides before actual competition. Lunge walk, buttock kicks and rotation torso from side to side are required for tennis players etc.

(i) Passive warming up:
In passive wanning up activities other than bodily movements are adapted to have physiological effects of warming up such as sauna bath, steam bath, massage, both with warm water etc.

2. Physical Wanning up:
In this, the psychological benefits of warming up are displayed with the effect of exercises. In this, mind is prepared for action within the duration of . warming up.

Question 9.
Write about the principle of uniformity and differentiation.
1. Principle of differentiation:
As we all know ‘no two individuals are alike, they may have different physical structure, psychological make up, interest, capacities and abilities etc. So, while preparing physical training programme, a coach or trainer must take into consideration these factors.

2. Principle of Uniformity:
The second principle for the sports training lies in the use and disuse of the trained skills. It simply implies that regular training or practice is most important for any training programme. Without regular practice or use of trained skill the training or fitness level is not possible to maintain at same level.

Question 10.
What is circuit training method? Write its benefits.
Circuit training was developed by R.E. Morgan and G.T. Anderson in 1953 at the University of Leads, England. This type of conditioning involves almost all of the training factors. Circuit training can be designed to develop strength, power, muscular endurance, speed, agility and neuromuscular coordination, flexibility and cardiovascular endurance.
Circuit training is formal type of training which is done in a circular pattern.

Circuit can be set up in gymnasium hall, room, or outside of the court and fields. There are usually six to ten stations are arranged in a circuit. A trainee perform one exercise and then move to the next station to do next exercise and keep moving from one point to the other to do the rest of exercises within the stipulated time.
Benefits of Circuit Training:
Circuit training has enormous advantages. These are mentioned below-

• It is time saving.
• More players can be trained at a time.
• Swiftness in training.
• Recreation in training.
• Development of individual capabilities.
• It is easy to make separate plans for men and women.
• It combines a number of different components of training.
• It provides an interesting training environment for the athlete and there are established times and levels to motivate the athlete to continue improving.
• The circuit can be modified to fit the needs of any one group or individual.
• It can be adapted within the time constraints of the individual.
• It can accommodate large groups of individuals at a relatively low expense.
• In circuit training progression in all activities is assured.

Question 11.
What is the meaning of cooling/limbering down?
It is very important process to bring the body in normal state after competition or training. These are simple, easy and mild exercises done after intense training to allow body from transition to resting phase or we can say that limbering down means lowering the intensity of the work by performing stretching exercise followed by deep breath and relaxation exercises.

Cooling down is a process, which should be carried out at the end of stemuos activity. Our body after an exercise or training period takes some time for coming to its normal state, during this period many accommodative activities take place inside the body. Blood circulation in effected muscles and joints take place at a faster pace and cools down slowly. Continuing with slow exercises and deep breathing, cooling down should be carried out. Sudden coming to rest posture shall cause immense harm to the joints and muscles of our body.
Methods of Cooling Down:

• Walking.
• Jogging 5-10 min.
• Static exercises 5-10 min.
• Stretching exercises 10-30 min.
• Yogic asana like shavasana.
• To take hot water bath.
• To carry out massage of the muscles to save them from hardening.
• To carry out entertainment activities or mood stimulating games.
• To carry out relaxation exercises.

The effects of cooling down are listed below:

• Assists in the decrease of post exercise stiffness and muscle soreness.
• Helpful in decreasing the risk of injury.
• Body temperature becomes normal.
• It reduces the chances of fainting.
• Supply good amount of oxygen.
• It decreases the level of underline in the blood.
• It relaxes muscles.
• Heart rate returns to initial stage.
• Decrease in tension.
• Save body from harmful effects.
• Calm down mental state.
• Reduces unwanted liquid from the muscle.
• Prepares the body for ensuing events.
• Reduces obstruction in the functioning of muscles.
• Makes the system favourable for other exercises.

Question 12.
What do you know about Interval method?
Interval training is very useful for increasing the endurance and capabilities of sprinters and other players. This pattern of training was developed by German coach Dr.Woldemar Gerschler and Dr. Herbert Reindel, Interval training method gives importance to distance, speed, time and rest and develops tolerance, strength and proper blood circulation towards heart.

In this, interval training- relatively fast runs over relatively short distances are repeated for a number of times. We can say, a player in this pattern runs half or a quarter of the fixed distance with maximum speeds and then followed by jogging to regain strength and repeats this pattern several times. As the player develops stamina, period of rest is reduced and running time with maximum speed is increased. This system of exercise is carried out on repeatedly till a player reaches the peak of his capacities.
1. Fast or Intensive Interval training
2. Slow or Extensive Interval training.

1. Fast or Intensive:
It is also called high intensity interval training (HUT) or sprint interval training (SIT) in which intense aerobic exercise with less period of recovery is given, until the athlete gets too exhausted to continue the workout. In this athlete performs 80 to 100% of his total capacity and the heart rate goes up to 170 to 200 beats/per minute. This method is primarily used to develop speed endurance.

2. Slow or Extensive:
It is primarily used to develop general endurance of an athlete. The minutes of repetition should be more with less intensity. In this athlete performs 60 to 80% of his total capacity and the heart rate increases upto 140-180 beats/per minute.

1. Interval training utilizes the body’s two energy- producing systems: The aerobic and the anaerobic.
(i) The aerobic system is the one that allows walking or running for several miles, that uses oxygen to convert carbohydrates from various sources throughout the body into energy.

(ii) The anaerobic system, on the other hand, draws energy from carbohydrates stored in muscles for short bursts of activity such as sprinting, jumping or lifting heavy objects. This system does not require oxygen, nor does it provide enough energy for more than the briefest activities.
2. It improves blood circulation.
3. Since, hardly any training aids are required; more athletes can be trained at the same time.
4. Economy of time.

PSEB 12th Class Physical Education Guide Sports Training Important Questions and Answers

Question 1.
Enlist various types of warming up.
(i) Physiological Warming up
(ii) Psychological Warming up.

Question 2.
What is the effect of cooling down?
Helpful in decreasing post exercise stiffness and muscle soreness.

Question 3.
When we should warm-up?
We should warm up prior to any activity or an event.

Question 4.
What is the another name for cooling down?
Limbering down.

Question 5.
Who developed the circuit training method?
R.E. Morgan and G.T. Anderson.

Question 6.
Name the person who developed interval training method.
German Coach Dr. Woldemar Gerschler and Dr. Herbert Reindel.

Question 7.
Enlist various types of Interval training method.

• Fast and intensive-intental -training.
• Slow and extensive interval training.

Question 8.
In which year the circuit training method was developed?
In the year 1953.

Question 9.
Enlist various exercises for wanning up.
Jogging, Strides, Stretching exercises, rotation movement exercises.

Question 10.
Enlist two principles of sports training.

• Principle of uniformity
• Principle of continuity.

Question 11.
Elucidate the meaning of term ‘circuit’?
Circuit means a circular pattern for the formal training.

Question 12.
Give the types of physiological warming up.

• Active warming up
• Passive warming up.

Question 13.
How many types of active warming up are there?
Two types.

Question 14.
Which type of warming up is general warming up?
Active warming up.

Question 15.
Which component is important under interval training method?
This method gives importance to distance, speed, duration and rest.

Question 16.
Which component of physical fitness is developed with interval training method?
Endurance.

Question 17.
What is circuit training?
Circuit training is formal type of training which is done in a circular pattern. Circuit can be set up in gymnasium hall, room, or outside of the court and fields. There are usually six to ten stations are arranged in a circuit. A trainee perform one exercise and then move to the next station to do next exercise and keep moving from, one point to the other to do the rest of exercises within the stipulated time.

Question 18.
Which component are included in circuit training?
Circuit training can be designed to develop strength, power, muscular endurance, speed, agility and neuromuscular coordination, flexibility and cardiovascular endurance.

Question 19.
How many stations can be there in circuit training?
6 to 10.

Question 20.
What percentage of efficiency in used under fast and intense interval training method?
80% to 100%.

Question 21.
At what level heart rate increases in fast and intense interval training method?
170 to 200 beats/per minute.

Question 22.
At what pace training is done under fast and intense interval training method?
In this method, training is done with fast pace for short distance.

Question 23.
At what pace training is done under slow and extensive interval training method?
In this method, speed is maintain at medium pac.

Question 24.
What percentage of efficiency is used under slow and extensive interval training method?
60 to 80%.

Question 25.
At what level heart rate increases in slow and extensive interval training method?
140 to 180 beats/per minute.

Question 1.
Give the meaning of sports training.
In general, the word sports training is commonly used by the sports person in the field of sports. But, in broad sense training may be defined as an organised and systematic instructional process which aims to improve the individuals’ physical, psychological and physiological performance or tactical capabilities.The scientific and systematic channel of preparation of players for highest level of sports performance is known as sports training.

Question 2.
What do you know about performance efficiency?
Performance efficiency largely depends on the rate of practice and the amount of the competition and training. It also depends on training of loads during practice, training period, and quality of training and equipment. Efficiency is not achieved over a day, it needs constant training under the supervision of coach.

Question 3.
What is the need of warming up?

• Increases temperature of muscles.
• Increases heart rate and blood flow.
• Enhances coordination and motor ability.
• Increases the sensitivity of nerve receptors.
• Lowering of the energy rates of metabolic chemical reactions.

Question 4.
Enlist methods of warming up.
Physiological warming up:
It is mainly when the light exercises are performed in order to have benefits of muscular contraction due to increase in temperature of the muscles.

Psychological warming up:
In this the psychological benefits of warming up are displayed with the effect of exercises. In this mind is prepared for action within the duration of warming up.

Question 5.
Define cooling down?
Cooling down is a process, which should be carried out at the end of stemuos activity. Our body after an exercise or training period takes some time for coming to its normal state, during this period many accommodative activities take place inside the body. Blood circulation in effected muscles and joints take place at a faster pace and cools down slowly. Continuing with slow exercises and deep breathing, cooling down should be carried out.

Question 6.
Highlight two advantages of cooling down.

• Assists in the decrease of post exercise stiffness and muscle soreness.
• Helpful in decreasing the risk of injury.

Question 7.
What is principle of rest in sports training?
This principle of training suggests that there should be sufficient rest and recovery period after the strenous work load. This is important so that one should feel fresh and recovered from fatigue to adopt further work load. In addition to rest and recover between the load it is also important that a person should take proper sleep, diet and rest before the training.

Question 8.

• Interval training utilizes the body’s two energy- producing systems: The aerobic and the anaerobic,
• Economy of time,
• Improves blood circulation.

Question 9.
Who developed the circuit training method?
Circuit training was developed by R.E. Morgan and G.T. Anderson in 1953 at the University of Leeds, England.

Question 10.
What is the purpose of interval training method?

• It gives importance to time, distance, speed and rest.
• It also develops endurance strength and improves blood circulation.

Question 11.
What is the aim of sports training?

• Improvement in work efficiency.
• Development of overall personality.

Question 12.
Give the examples of specific warming up in football sport.
Lunge walk, side steps, running backward, buttock kicks and chest hugs are required in football.

Question 13.
Stick rotation dribbing, tapping etc. specific warming up in related to which sport?
Hockey.

Question 1.
Write a note on the following:
(a) Physical training
(b) Technical skill.
(a) Physical training:
Physical training refers as one must possess physical fitness components e.g. strength, speed, endurance, agility, balance, power etc. these components can be achieved through regular physical training and are prerequisites of all sports. These physical fitness components vary from sports to sports e.g. some sports requires strength and endurance and other needs agility etc. With the help of physical training plan e.g. short term and long term plan, plan according to participation in general or specific competitions etc. can be achieved easily.

(b) Technical skill:
Technical skill is a fundamental component of sports training. It refers to improve set of exercises and various skills used in various sports to achieve highly optimum performance or efficiency. Technical skill consists of various repeats (in order to become skill), initial training of athlete, abilities of athlete, motor abilities (fitness components), sensory abilities (understanding level of complex situation) etc. these above said fundaments can be achieved regular practice. For this, technical skill can divide in phases e.g. athlete must be prepared themselves for physical fitness, skill improvement training etc.

Question 2.
Write about principles of continuity and uniformity.
1. Principle of continuity:
The second principle for the sports training lies in the use and disuse of the trained skills. It simply implies that regular training or practice is most important for any training programme. Without regular practice or use of trained skill the training or fitness level is not possible to maintain at same level.

2. Principle of uniformity:
As we all know ‘no two individuals are alike, they may have different physical structure, psychological make up, interest, capacities and abilities etc. So, while preparing physical training programme, a coach or trainer must take into consideration these factors.

Question 3.
Give an account of wanning up exercises.

• Jogging
• Strides
• Stretching exercises
• Rotation movement exercises
• Wind sprint
• Walking lunge
• Butt kicks

Question 4.
What do you mean by principle of active participation?
Active participation means where an, athlete or sportsperson have a keen interest or willingness to take part in a particular activity. Any training programme proves to be of no use if the person is not willing or ready to take part in that very activity. So, this is the most valuable principle of training that a person should be ready in terms of interest, his physical or physiological abilities and capabilities to take any training programme.

Question 5.
Explain principles of rest and recovery.
This principle of training suggests that there should be sufficient rest and recovery period after the strenous work load. This is important so that one should feel fresh and recovered from fatigue to adopt further work load. In addition to rest and recover between the load it is also important that a person should take proper sleep, diet and rest before the training.

Question 6.
This principle implies that after performing severe exercise or training programe for weeks our body becomes adjustable to increased or decreased physical demands. So, in order to have continued improvement the training programme should be such that new routine is introduced after adaptation to previous level of training or particular exercise.

Question 7.
Elucidate advantages of circuit training method.

• It is easy to make separate plans for men and women.
• It combines a number of different components of training.
• It provides an interesting training environment for the athlete and there are established times and levels to motivate the athlete to continue improving.
• The circuit can be modified to fit the needs of any one group or individual.
• It can be adapted within the time constraints of the individual.

Question 1.
What is the meaning of cooling down? Explain about the effects of cooling down on body.
It is very important process to bring the body in normal state after competition or training. These are simple, easy and mild exercises done after intense training to allow body from transition to resting phase or we can say that limbering down means lowering the intensity of the work by performing stretching exercise followed by deep breath and relaxation exercises.

Cooling down is a process, which should be carried out at the end of stemuos activity. Our body after ah exercise or training period takes some time for coming to its normal state, during this period many accommodative activities take place inside the body. Blood circulation in effected muscles and joints take place at a faster pace and cools down slowly. Continuing with slow exercises and deep breathing, cooling down should be carried out. Sudden coming to rest posture shall cause immense harm to the joints and muscles of our body.

Following are the benefits of cooling down:

• Assists in the decrease of post exercise stiffness and muscle soreness.
• Helpful in decreasing the risk of injury.
• Body temperature becomes normal.
• It reduces the chances of fainting.
• Supply good amount of oxygen.
• It decreases the level of aderaline in the blood.
• It relaxes muscles.
• Heart rate returns to initial stage.
• Decrease in tension.
• Save body from harmful effects.
• Calm down mental state.
• Reduces unwanted liquid from the muscle.
• Prepares the body for ensuing events.
• Reduces obstruction in the functioning of muscles.
• Makes the system favourable for other exercises.

Question 2.
What do you mean by warming up? How should body be wanned up? Explain various methods of warming up.
Toning up of the muscles by performing warming up exercises, is most essential before starting with any physical workout. Warming up here means ‘preparing the physical body for the type of physical work it is going to do, by giving some kind of physical exercises. It is normally seen that stemuos physical exercises are started without doing any warming up exercises, which causes harmful effects on the related muscles and at times may result in to serious injury. Warming up exercises is required for preparing the body for proper demonstration of the skills. These exercises prepare a player physically and mentally for the event.

Definitions of Warming Up:
“Warming up is a preliminary exercises of physical and mental preparation for a strenuous exertion”.
“Warming up is a process of heating the whole body by running and performing exercises prior to the activity”.
“Warming up is a process by which human machine is brought to a condition at which it safely responds to the nerves impulses of the persons for quick and efficient action”.
“Warming up is done to tone up the body so as to meet the ensuing activity”.
Warming up is very essential before any competition or other activities though muscles can be damaged or tom which is lead to disability or inefficiency in sports.

Types of Warming Up:
Types of Warming up: The types of warming up can broadly be classified as follows:

1. Physiological warming up:
It is mainly when the light exercises are performed in order to have benefits of muscular contraction due to increase in temperature of the muscles. It can furthur be classified into following two categories:
(i) Active warming up. It involves bodily movement such as light exercises, jogging etc. to increase body temperature.
It is furthur of two types:
(a) General warming up
(b) Specific warming up

(a) General warming up:
In this type of warm-up athlete does not engage themselves in a specific activity. It generally last from eight to ten minutes. This warm-up might include very easy jogging or vigorous walking, strides and simple exercises which are helpful to increase the heart rate. It also improves coordination and flexibility of joints. In general warm up, there are no such specific criteria but there are few exercises which may be mandatory for increasing temperature of the muscles. These are as follows:

• Jogging
• Strides
• Stretching exercises
• Rotation movement exercises
• Wind sprint
• Walking lunge
• Butt kicks High knee pulls
• Backward step over
• Jumping jacks
• Run forward, backward and sideward
• Exercises for hands, arms, shoulder, neck, knees and legs.

(b) Specific warming up:
In this type of warming up athlete must follow specific exercises related to game or activity. For example sprinter must do strides before actual competition. Lunge walk, buttock kicks and rotation torso from side to side are required for tennis players etc. It stimulates competition actions and intensity in order to start the competition at the highest level. We have few examples of specific exercises related to game as follows:

• Lunge walk, side steps, running backward, buttock kicks and chest hugs are required in football.
• Lunge walk, buttock kicks, controlled leg swings and fast feet for runners.
• Jog on the spot, jumps from side to side; lunge forward and backward for cyclist.
• Lunge walk, buttocks kicks, jumping high and from side to side and rotating torso are for tennis.
• Dribbling, shooting and lay up shots for basket ball.
• All types of bending exercises and body twisting for badminton.

(ii) Passive wanning up:
In passive warming up activities other than bodily movements are adapted to have physiological effects of warming up such as sauna
bath, steam bath, massage, both with warm water etc.

2. Psychological Wanning up:
In this, the psychological benefits of warming up are displayed with the effect of exercises. In this, mind is prepared for action within the duration of warming up. The following ways can be adopted for the psychological warming up:

• With the help of pep talks.
• Motivational techniques
• Meditation and relaxation training.

Question 3.
Write the meaning of Interval training method. Briefly explain various purposes of interval training method.
Interval training is very useful for increasing the endurance and capabilities of sprinters and other players. This pattern of training was developed by German coach Dr.Woldemar Gerschler and Dr. Herbert Reindel, Interval training method gives importance to distance, speed, time and rest and develops tolerance, strength and proper blood circulation towards heart.

In this, interval training- relatively fast runs over relatively short distances are repeated for a number of times. We can say, a player in this pattern runs half or a quarter of the fixed distance with maximum speeds and then followed by jogging to regain strength and repeats this pattern several times. As the player develops stamina, period of rest is reduced and running time with maximum speed is increased. This system of exercise is carried out on repeatedly till a player reaches the peak of his capacities.

1. Interval training utilizes the body’s two energy- producing systems: The aerobic and the anaerobic.

(i) The aerobic system is the one that allows walking or running for several miles, that uses oxygen to convert carbohydrates from various sources throughout the body into energy.

(ii) The anaerobic system, on the other hand, draws energy from carbohydrates stored in muscles for short bursts of activity such as sprinting, jumping or lifting heavy objects. This system does not require oxygen, nor does it provide enough energy for more than the briefest activities.

2. It improves blood circulation.
3. Since, hardly any training aids are required; more athletes can be trained at the same time.
4. Economy of time.
Purpose of the Interval training method

Improves anaerobic performance:
Adapt the body to running condition, including high pace and high levels of lactase in muscles. Accomplish more overall work with less physiological strain in comparison to continuous running.

Question 4.
What is the meaning of sports training? Briefly explain principles of sports training.
Meaning and Definition of Sports Training:
In general, the word sports training is commonly used by the sportsperson in the field of sports. But, in broad sense training may be defined as an organised and systematic instructional process which aims is to improve the individual’s physical, psychological and intellectual performance or tactical capabilities. It can be said that, ‘the means with which a sports person is prepared physically, technically, tactically, intellectually, psychologically and morally is called sports training.

The scientific and systematic channel of preparation of players for highest level of sports performance is known as sports training. All the learning influences and processes that are aimed at enhancing sports performance.
are considered to be an important part of sports training. .

Definition of Sports Training:
Various experts have defined the concept of sports training in different ways. Some of the definitions are as follows:
According to Matveyev, “the fundamental form of an athlete’s training is called sports training. It is an organised process of controlling a player’s development with the help of systematically organised exercises”. There are several universally accepted scientific training principles that must be followed in order to improve conditions and sports performance. These training principles are as follows:

1. Principle of differentiation:
As we all know ‘no two individuals are alike’, they may have different physical structure, psychological make up, interest, capacities and abilities etc. So, while preparing physical training programme, a coach or trainer must take into consideration these factors.

2. Principle of Continuity:
The second principle for the sports training lies in the use and disuse of the trained skills. It simply implies that regular training or practice is most important for any training programme. Without regular practice or use of trained skill the training or fitness level is not possible to maintain at same level.

In order to improve the level of performance, the overload i.e. load greater than normal stress must be given properly. It should be done in a systematic way. The load should be increased gradually after adapting certain training level.

4. Principle of safety and prevention:
It is important to take care of every aspect related to safety such as size and specification of equipment, classification of students, warming up and protective equipment etc. to avoid chances of injuries during training. As we all know prevention is better than cure, so we should always consider these aspects while training.

5. Principle of variety:
In order to maintain the zeal and interest for the activity it is important to provide variety in the training method. The monotonous and same kind of training would bring boredom and lack of interest to continue training for the same activity. So, its necessary to change the training method to create interest for the activity.

6. Principle of periodization:
The term periodization can be described as the division of training session to attain peak performance at the time of competition. So, this is the scientific base of training, in which lots of expertise is required to design training programme to attain highest performance at the time of competition. Broadly, the periodization can be distinguished as preparatory phase, competition phase and transition or recovery phase.

7. Principle of progression:
This principle of training implies that training must proceed from simple to complex and general to specific e.g. firstly simple dribbling should be practiced in order to perform lay up shot in basketball. The basic skills should be trained first in order to create stronger base for the particular activity. It should be done slowly and gradually to attain highest performance.

8. Principle of rest/recovery:
This principle of training suggests that there should be sufficient rest and recovery period after the strenous work load. This is important so that one should feel fresh and recovered from fatigue to adopt further work load. In addition to rest and recover between the load it is also important that a person should take proper sleep, diet and rest before the training.

This principle implies that after performing severe exercise or training programe for weeks our body becomes adjustable to increased or decreased physical demands. So, in order to have continued improvement the training programme should be such that new routine is introduced after adaptation to previous level of training or particular exercise.

10. Principle of active participation:
Active participation means where an athlete or sportsperson have a keen interest or willingness to take part in a particular activity. Any training programme proves to be of no use if the person is not willing or ready to take part in that very activity. So, this is the most valuable principle of training that a person should be ready in terms of interest* his physical or physiological abilities and capabilities to take any training programme.

Sports Training PSEB 12th Class Physical Education Notes

In today’s competitive world of sports, everyone aims at winning at all cost. Hence, the concept of sports training has a vital role to play in the field of sports. The concept sports training deals with the systematic preparation of athletes to obtain peak performance at the time of competition. The aim of sports training is to produce optimum performance during competition.

Hence, the training schedule is classified in such a way that a player gets complete recovery from the training load and feels fresh and energetic to take fresh load to continue performance. According to Martin, “Sports training is a planned and controlled process of achieving goals in which the changes of motor performance and behaviour are made through measures of content, method and organisation.

Hence, sports training implies systematic and controlled way of imparting training to an athlete to produce optimum performance at the time of competition. In order to have fruitful results from the sports training programme various principles such as individual differences, principle of use of disuse, load (overload), progression, safety, continuity and rest or recovery must be followed, otherwise the purpose of training will not be effective and useful for the trainees.

It is also important to perform warm up exercise to prepare an athelete physically, physiologically or psychologically for the sports training programme or prior to competition. It helps an athlete to perform with least chances of injuries. Similarly, limbering or cooling down plays a significant role to attain normal condition after performing stemuos exercises. Hence, sports training is the ways and means of systematic training to develop various components of physical fitness to attain optimal performance during competition.

Punjab State Board PSEB 12th Class Physical Education Book Solutions Chapter 2 Sports Training Textbook Exercise Questions and Answers.

## PSEB Solutions for Class 10 Welcome Life Chapter 1 Self-Awareness and Self Discipline

Welcome Life Guide for Class 10 PSEB Self-Awareness and Self Discipline Textbook Questions and Answers

Choose True/False

1. Repeated practice sharpens the skills.
True

2. Singing can be refined with practice.
True

3. Skills are given to lucky people by birth. He who has not got his boon cannot do anything.
False

4. Talent should also be trained to be carved.
True.

Think and Tell

Question 1.
Upon which thing, a good choice of career depends?
The choice of a good career depends on one’s own inclination that in which field he is most inclined. If a person chooses a career that he does not like, then that career will not be good for him. It also depends on the circumstances of the person’s home and the need of the hour which career he chooses.

Question 2.
How many types of counseling did the career counselor suggest?
The career counselor suggested three types of counseling

• Personal Counselling. When a counselor councils an individual personally, it is called personal counseling.
• Group counseling. When some students or individuals interact with a counselor, it is called group counseling.
• Class counseling. When the counselor talks to the whole class together and tells them about their career choices, it is called class counseling.

Question 3.
About which thing Navdeep was happy?
Navdeep was happy that the school is now doing well as the students are being made career conscious.

Question 4.
Nowadays, why is it become good to move with a lot of career options?
Nowadays, it is becoming good to move with a lot of career options because :

• Maybe the person may lose interest in that occupation in the near future.
• It is possible that in the future, the importance of a particular career in society will be lost.
• Maybe in another job, a person starts to get self-satisfaction and more money.

Question 5.
What good things do you notice in your school?

• Our school focuses on the multifaceted development of students.
• Students are introduced to a range of future career choices.
• Students are told to think not just about one career but about at least three career options.
• The school teachers have a good relationship with the children and counsel them from time to time.

Question 6.
Which quality do you find in Manisha?
In Manisha, we saw the quality of knowing. She wanted to know why the kids were asked to fill three choices in the form. This quality should be in every child that why should he do any work. The advantage of this is that the child develops the quality of rational thinking.

PSEB 10th Class Welcome Life Guide Self-Awareness and Self Discipline Important Questions and Answer

Multiple Choice Questions:

1. Skill conies with ………….. in person.
(a) Practice
(b) Study
(c) Wandering
(d) All of these
(a) Practice

2. How can we improve one’s singing skills?
(a) By learning songs
(b) By practice
(c) By listening to songs
(d) None of these
(b) By practice

3. How to find someone’s skills?
(a) With hard work
(b) With a concentration
(c) With practice
(d) All of these
(d) All of these

4. Human nature is …………..
(a) changeable
(b) same
(c) static
(d) none of these
(a) changeable

5. An individual with narrow mindedness :
(b) Never becomes happy
(c) Never accepts criticism
(d) All of these
(d) All of these

6. An individual’s thinking :
(a) should be open
(b) should be closed
(c) should be same
(d) should be unsatisfied
(a) should be open.

7. Which of these is a feature of a good personality?
(a) Sociable
(b) Accept the challenge
(d) All of these
(d) All of these

8. Everyone must keep ………………… career options.
(a) Two
(b) Three
(c) Four
(d) Five
(b) Three

9. Which of these is a type of counseling?
(a) Individual
(b) Class
(c) Group
(d) All of these
(d) All of these

10. One must choose a career according to his
(a) Ability
(b) Interest
(c) Needs
(d) All of these
(d) All of these

Fill in the Blanks:

1. Varinder Kumar was a teacher and a ………………. as well.
Counselor

2. One must keep …………… career options.
three

3. An individual’s ……………… nature becomes an obstacle in the way of his progress.
rigid

4. ………………. has given great progress to society;
Technology

5. …………………. is the law of nature.
Change

True / False:

1. A narrow-minded person always makes progress.
False

2. Not every child is skilled.
False

3. Practice enhances one’s skills.
True

4. An individual should openly accept his own criticism.
True

5. Individuals should choose a career according to their interests.
True

Match the Column:

 Column A Column B (a) Talent (i) Trend (b) Foreigner (ii) Quality (c) Point of view (iii) British (d) Personality (iv) Outlook (e) Interest (v) Individual’s outlook

 Column A Column B (a) Talent (ii) Quality (b) Foreigner (iii) British (c) Point of view (iv) Outlook (d) Personality (v) Individual’s outlook (e) Interest (i) Trend

Question 1.
What makes a Person Special?
The skills presented in a person make him a person special from the ordinary.

Question 2.
How do a person’s skills shine?
A person’s skills shine only with practice.

Question 3.
How can we improve one’s singing skills?
The singing skills of an individual can be improved only with continuous practice.

Question 4.
What is needed to improve a person’s talent?
Continuos practice, hard work, and concentration can improve one’s talent.

Question 5.
What kind of human nature should it be?
Human nature must be changeable.

Question 6.
Give one demerit of narrow-mindedness.
A narrow-minded person always spreads negativity.

Question 7.
What is the advantage of open-mindedness?
An open-minded person always remains happy and keeps others happy.

Question 8.
Can a narrow-minded person maintain a relationship?
No, he cannot maintain a relationship.

Question 9.
What is meant by openness?
Openness is the quality of one’s nature that helps, us to think openly.

Question 10.
Give one quality of an open-minded person.
An open-minded person is always sociable.

Question 11.
Give one flaw in a narrow-minded person.
He is critical of everything.

Question 12.
How can the stubborn nature of a person is detrimental to him?
Because stubborn nature becomes an obstacle in the way of his progress.

Question 13.
What kind of stubbornness should the person have?
The stubbornness of doing work with honesty, hard work, not to take a bribe, etc.

Question 14.
How can we become responsible citizens of society?
By following social rules and removing wrong things from society, we can become responsible citizens.

Question 15.
How many career options a person should have?
He must have a minimum of three career options.

Question 16.
What should a person keep in mind while choosing a career?
His interest and need of the hour.

Question 1.
How can we master a task? Explain with an example.
Every person has some other skill and there is a need to polish that skill. To polish one’s skill, there is a need to do the practice. One cannot be a master of a skill if he is short of practice. For example, the writing of a first-class student can never be good but can be after writing continually. As children, we did not know how to ride a bicycle but with practice, we learned to ride a bicycle. In this way, practice is a must to masterwork.

Question 2.
What should a person keep his mind open?
A person must keep his mind and perspective open. As the saying goes, running water looks good but stagnant water becomes dirty. In the same way, a narrow-minded person cannot make progress in life. He neither makes himself happy nor allows others to be happy. He can’t even handle relationships properly. He never accepts his criticism which actually he should do. One should keep his thinking open and must accept criticism positively.

Question 3.
What are the benefits of being open-minded?

• An open-minded person always accepts a change.
• He accepts his criticism positively and brings changes in himself.
• He contributes to social progress and does his own progress as well.
• He keeps himself happy and keeps others happy too.
• Does he maintain relationships in a better way?

Question 4.
What is the role of technology in our lives?
Nowadays new technology is coming before us and we own it in a positive manner. Life is constantly progressing with technology. The older generation is not as fast as today’s youth in adopting modem technology. That’s why today’s generation is progressing so fast with this technology, we can do all our work easily. For example., clothes used to be washed by hand but now the machine washes them easily. In this way, we can say that technology plays a very important role in our lives and makes our work quite easy.

Question 5.
“The person should be stubborn or flexible”, Give a reason in favor of your answer.
The person should not be stubborn but flexible in nature. His stubbornness becomes an obstacle in the way of his progress such as not accepting boys and girls as equals. People start to discriminate and pay a heavy price for it. Such stubbornness should be changed. One can contribute to the family’s progress, society’s progress, and national progress by changing according to changed circumstances.

Question 6.
What are the duties of a responsible citizen?

• He must change himself according to changed circumstances.
• He must not accept Social evils. Instead, he must try to eliminate them.
• He must remain within social boundaries.
• He must motivate others to follow social rules.
• He must try to bring social change and change himself as well.

Question 1.
Give merits and demerits of an individual’s personality.
Merits.

• First of all, he must be ready to learn something new so that he could change himself according to changed circumstances.
• He must be sociable and keep healthy relationships with others.
• He must accept every challenge because if he will not, he will become static and will not be able to do individual progress.
• He must follow all the social rules and must motivate others to do the same.

Demerits.

• A stubborn person never takes anyone’s advice. He always does his own thing which is to his detriment.
• A stubborn person always runs away from his responsibilities which can be harmful to his life.
• He gets angry suddenly which can be dangerous.
• He loses his temper very quickly.
• Many times, he never follows the rules. Instead, he breaks the social norms.

Question 2.
Observe the following pictures and answer the given questions.

1. What is shown in picture 1?
2. What do you observe in picture 2?
3. What do we come to know from both the pictures?

1. Picture 1 tells us about a person with narrow-mindedness. He always remains unhappy. He not only hurts himself but also hurts those around him. He cannot maintain his relationships as well.

2. Person in the second picture is of open thinking and nature who always accepts a change. He himself remains happy and keeps others happy as well. He maintains his relationships well.

3. After looking at both the pictures, we can say that an individual must not be stubborn but be of open mind and perspective. It makes his life happy. On contrary, the stubborn person remains sad every time which is not correct. So, we must take a vow that We must accept challenges and will remain happy.

Self-Awareness and Self Discipline PSEB 10th Class Welcome Life Notes

• Every individual is having some talent and this talent can be of any type.
• There is definitely a need to polish the talent which an individual possesses and it can be polished through repeated practice.
• To become a master of any work, repeated practice is a must. Without practice, no one can do any work in a proper way. That’s why practice is one of the means to polish someone’s talent.
• Humans and their nature, both are changeable. The way in which change comes in nature, in the same way, the nature of an individual also changes with time.
• An individual must be of flexible attitude and must welcome every change. A person with a rigid attitude cannot remain happy and make others unhappy as well.
• A person with a rigid attitude cannot handle his relationships well. He cannot hear his criticism. An individual must develop quality within himself of listening to his criticism and must change that aspect of his life for which he is being criticized.
• An open-minded individual accepts every change with an open heart and does progresses in life. Open-minded person adapts himself according to the changed situation and does progress. If we have adopted modem technology, it is because of our open-mindedness.
• An individual must not be of rigid attitude. Instead, he must be of flexible nature. If something is going wrong around us, we must try to improve it so that our future generations do not have that problem.
• Everyone must work to become responsible citizenship and must accept everything that comes in his way.
• The most important thing is for the person to see his tendency. A person should work in the same field in which he is inclined otherwise he will not be able to do any work properly. After seeing the trends, he should work hard in that field. In this way, he will become aware of the career to come.

Punjab State Board PSEB 10th Class Welcome Life Book Solutions Chapter 1 Self-Awareness and Self Discipline Textbook Exercise Questions and Answers.

## PSEB 10th Class Computer Science Notes in English Medium

• Chapter 1 Office Tools Notes
• Chapter 2 HTML Fundamentals Notes
• Chapter 3 HTML II Notes
• Chapter 4 Web Development Notes
• Chapter 5 Desktop Publishing Notes
• Chapter 6 Operating Systems Notes
• Chapter 7 Microsoft Publishers-I Notes
• Chapter 8 Microsoft Publishers-II Notes

Punjab State Board Syllabus PSEB 10th Class Computer Science Notes Pdf in English Medium and Punjabi Medium are part of PSEB Solutions for Class 10.

## PSEB Solutions for Class 8 Science Chapter 16 Light

PSEB 8th Class Science Guide Light Textbook Questions and Answers

Exercises

Question 1.
Suppose you are in a dark room. Can you see objects in the room ? Can you see objects outside the room ? Explain.
No, we cannot see anything in dark. As no light is falling on the objects in the room and they are not emitting any light on their own. So, nothing is visible inside the dark room.
Objects outside the room can be seen, if either there is light outside the room or objects are emitting their own light.

Question 2.
Differentiate between regular and diffused reflection. Does diffused reflection mean the failure of the laws of reflection ?
Differences between regular reflection and diffused reflection:

 Regular reflection Diffused reflection 1. It occurs on a smooth, plane surface. 1. It occurs on a rough, irregular surface. 2. Reflected rays are parallel to one another. 2. Reflected rays are unparallel to each other.

Diffused reflection is not failure of laws of reflection. It is only due to irregularities on the reflecting surface.

Question 3.
Mention against each of the following whether regular or diffused reflection will take place when a beam of light strikes. Justify your answer in each case.
[a] Polished wooden table
[b] Chalk powder
[c] Cardboard surface
[d] Marble floor with water spread over it.
[e] Mirror
[f] Piece of paper.
(a) Polished wooden table. Regular reflection, as wooden table has smooth polished surface.
(b) Chalk powder. Diffused reflection due to rough surface of chalk powder.
(c) Cardboard surface. Diffused reflection because cardboard has small irregularities on its surface.
(d) Marble floor with water spread over it. Regular reflection as water gives a smooth surface.
(e) Mirror. Regular reflection due to smooth surface.
(f) Piece of paper. Regular reflection if paper is fine and diffused reflection if paper is coarse.

Question 4.
State the laws of reflection.
Laws of reflection.

1. Angle of incidence (∠i) = Angle of reflection ( ∠r).
2. Incident ray, reflected ray and the normal at the point of incidence all lie in the same plane.

Question 5.
Describe an activity to show that the incident ray, the reflected ray, normal, the point of incidence lie in the same plane.
Experiment.
Take a white sheet, spread it on a table. Draw a line MM on it. Place a plane mirror vertically on this line. Now throw light on a comb in this ways that a parallel light rays fall on the mirror. Adjust it in such a way that a beautiful pattern of incident and reflected rays is formed. Now mark points A, B, C on incident ray and points D, E, F on its corresponding reflected ray. Switch off the torch and remove the mirror. Join the points and extend line to mirror. ABC will meet MM at O and DEF will all also be meeting at O. OA is incident ray and OF is reflected ray. Draw ON ⊥ MM .

Measure the angle of incidence ∠AON and the angle of reflection ∠FON which would found to be equal. Incident ray, reflected ray and normal, all lie in one plane of paper.

Question 6.
Fill in the blanks in the following.
(a) A person 1 m in front of a mirror seems to be ……………….. m away from his image.
(b) If you touch your ………………….. ear with right hand in front of a plane mirror it will be seen that your right ear is touched with ……………… .
(c) The size of pupil becomes …………………. when you in dim light.
(d) Night birds have ………………. cones than rods in their eyes.
(a) 2m
(b) Right, Left
(c) large
(d) more.

Choose the correct option in the Questions 7-8.

Question 7.
Angle of incidence is equal to angle of reflection
(a) Always
(b) Sometimes
(c) Under special conditions
(d) Never.
(a) Always.

Question 8.
Image formed by a plane mirror is
(a) virtual, behind the mirror and enlarged.
(b) virtual, behind the mirror and of same size as the object.
(c) real at the surface of mirror and enlarged.
(d) real, behind the mirror and of same size as the object.
(b) Virtual, behind the mirror and of same size as the object.

Question 9.
Describe the construction of a Kaleiodeoscope.

Construction of a Kaleiodeoscope. It is a toy to form many images by multiple reflections. A Kaleiodeoscope is made up of three strips of plane mirrors inclined at angles of 60° enclosed in a tube. One end of tube has a ground glass plate with a clear glass plate on its inner side. A metallic ring separates the two plates and the space is filled with coloured pieces of glass or broken bangles. A cardboard with a hole in the centre is fixed on the other end of the tube.

Question 10.
Draw a labelled sketch of the human eye.
Labelled diagram to show different parts of human eye.

Question 11.
Gurmit wanted to perform activity 16.8 using a laser torch. Her teacher advised her not do so. Can you explain the basis of the teacher’s advice ?
Laser torch has very sharp beams of light which can destroy the pupil or retina of the eye.

Question 12.
Explain how can you take care of your eyes.
Care of eyes.
Eyes are the most precious gifts of nature. So we should take full care of our eyes by taking atleast following precautions.

1. We should wash our eyes daily with clean water.
2. We should not read or work in very bright or dim light.
3. We should not read in a running vehicle.
4. We should not rub our eyes.
5. We should use sunglasses on hot summer day.
6. We should not look directly at the sun. Also we should not look at the sun during solar eclipse.
7. We should eat vitamin A rich food for healthy, clear eyes.

Question 13.
What is the angle of incidence of a ray if the reflected ray is at an angle of 90° to the incident ray ?
Solution:

If ∠i = angle of incidence
∠r = angle of reflection
∠i + ∠r = 90 (given)
But ∠i = ∠r
(According to laws of reflection)
∴ ∠i + ∠i = 90°
2 ∠i = 90
∠r = ∠i – 45°

Question 14.
How many images of a candle will be formed if it placed between two parallel mirrors separated by 40 cm ?

When mirrors are separated by 40 cm and are parallel to each other so that the angle between the mirrors is 0° which is not sulj-multiple of 360°. Then theoretically, the number of images formed would be infinite, but as a considerable amount of light is lost due to reflections so only a limited number of images are seen which is shown in figure.

Question 15.
Two mirrors meet at right angles. A ray of light is incident on one at an angle of 30° as shown is figure. Draw the reflected ray from the second mirror.

Solution:

Question 16.
Bhoojo stands at A just on the side of a plane mirror as shown in figure. Can he see himself in the mirror ? Also can he see image of objects situated at P, Q and R ?

Solution:
Bhoojo cannot see his image in the mirror as he is standing outside the edge of mirror. He can see the images of P and Q easily but not the image of R.

Question 17.
(a) Find out the position of image of an object situated at A in plane mirror.
(b) Can Paheli at B see this image ?
(c) Can Bhoojo at C see this image ?
(d) When Paheli moves from B to C where does the image of A move ?

(a) The image of A in the mirror will be as far behind as the object in front of the mirror.
(b) Yes, Paheli can see the image.
(c) Yes, Bhoojo can see this image.
(d) When Paheli moved from B to C, the image of A will not move forward.

PSEB Solutions for Class 8 Science Light Important Questions and Answers

Multiple Choice Questions

Question 1.
The plane and polished surface that returns light falling on it in the same direction or any other direction is called:
(a) Lens
(b) Prisom
(c) Mirror
(d) Kaleidoscope.
(c) Mirror.

Question 2.
How many colours are present in white sunlight ?
(a) 2
(b) 5
(c) 7
(d) 3.
(c) 7.

Question 3.
What is the most convenient distance for reading by a normal eye ?
(a) 10 cm
(b) 25 cm
(c) 15 cm
(d) 20 cm.
(b) 25 cm.

Question 4.
When you see in dim light the size of your pupil becomes:
(a) Small
(b) Large
(c) Neither small nor large
(b) Very small.
(b) Large.

Question 5.
The Phenomena of splitting of light into its constituent colours is called:
(a) Reflection
(b) Refraction
(c) Dispersion
(b) Combination.
(c) Dispersion.

Question 6.
The eye lenses focuses:
(a) On Cornea
(b) On Retina
(c) On Iris
(d) None of these.
(b) On Retina.

Question 1.
Can any one see in the dark ?
No.

Question 2.
It is what that helps us to see objects ?
Light.

Question 3.
Name any two Luminous bodies.

1. Sun
2. Electric bulb.

Question 4.
Is moon a luminous or a non-luminous body ?
Non-luminous.

Question 5.
Where is a reflection seen ?
In mirror.

Question 6.
Which surface can act as a mirror ?
Any polished and smooth surface.

Question 7.
If you are standing in front of a mirror and observing your own image what is the relation between the distance of the object and the image from the mirror ?
Distance of object from the mirror = Distance of image from the mirror.

Question 8.
What is the angle of reflection, when a ray of light is incident normally on a plane mirror ?
Zero.

Question 9.
Name two objects which split white light into many colours.
Water bubbles, surface of CD, prism.

Question 10.
Name the seven colours of light.
Red, orange, yellow, green, blue, indigo and violet.

Question 11.
Give one example of dispersion of light in nature.
A rainbow.

Question 12.
Is focal length of eye lens fixed ? If not, why ?
No. Eye lens has variable focal length. Focal length of Eye lens varies due to action of ciliary muscles.

Question 13.
What is the function of sclerotic in human eye ?
Sclerotic provides a solid shape to the eye and protects it from external injuries.

Question 14.
What is the function of ciliary muscles in human eye ?
Eye lens is held in its position by ciliary muscles. Ciliary muscles help the eye lens to change its focal length by adjusting its curvature.

Question 15.
What is the function of rods on the retina ?
Rods are sensitive to intensity of light. The more the intensity of light, more are they excited.

Question 16.
What are cones ?
Cones on retina are sensitive to different colours. If cones are absent or insufficient, the person is colour blind.

Question 17.
What is basic cause of colour blindness ?
It is due to absence or insufficient number of cones on the retina. Seeing sun or towards it during solar eclipse may cause colour blindness.

Question 18.
Why cats and bats are able to see at night ?
They have very large number of rods on retina. Hence, they are able to see even a small quantity of light.

Question 19.
At what rate the images pass one after the other on a cinema screen ?
25 or more per second.

Question 20.
What type of photosensitive cells are present on the retina of the eye ?
Cones and rods.

Question 21.
Name one device that can be used by short statured person to see over the head of a crowd.
Periscope.

Question 22.
Find out the letters of English alphabet or any another language known to you in which the image formed in a plane mirror appears exactly like the letter itself.

Question 1.
What are luminous and non-luminous bodies ? Give examples.
Luminous Bodies.
Those objects which emit their own light, are called luminous bodies e.g. sun, stars, burning fire, radium etc.

Non-luminous Bodies.
Those objects which do not emit light of their own but shine due to other luminous bodies, are called Non-Luminous bodies. They are visible only, when light falls on them.
e.g. Moon, earth and other planets, things in a room.

Question 2.
How do we see objects ?
When light from a light source falls on any object, it is scattered by it. The scattered light enters our eyes to form the image of the object and the object is, thus, seen.

Question 3.
Give the conditions necessary for seeing an object.
Conditions for Seeing Objects. To see an object, the following three conditions are required to be satisfied:

1. Source of light to make object visible
2. The object
3. Eye sight.

Question 4.
What is a virtual image ? Give one situation where a virtual image is formed.
Virtual image.
An image, which cannot be obtained on a screen, is called a virtual image. Virtual image is formed when reflected rays do not actually meet at a point.
Image formed in a plane mirror is always virtual.

Question 5.
What do you understand by lateral inversion ?
Lateral Inversion.
In a plane mirror, the right side of the object becomes left side of the image and the left side of the object becomes right side of the image. That is the image is sideways inverted. This phenomenon, is called lateral inversion.

Question 6.
State the laws of reflection of light.
Laws of reflection.
The reflection at the smooth surface is found to obey the following two laws, called the laws of reflection.

1. The angle of incidence is equal to the angle of reflection
i.e., ∠i – ∠r.
2. The incident ray, the reflected ray and the normal at the point of incidence lie in the same plane.

Question 7.
What is diffused reflection and regular reflection ?
Diffused Reflection.
It takes place when the surface is not smooth or polished e.g., wall, paper. The rays reflected from an uneven surface are not parallel but scattered in all directions and such reflection is called diffused reflection.

Regular Reflection.
It takes place when a beam of light falls on a smooth and polished surface, e.g., a mirror. The reflected rays from an even surface form a clear image.

Question 8.
What do you understand by reflection of light ?
Reflection of light.
When a ray of light falls on a mirror, or polished surface, it is sent back in a particular direction obeying certain laws of reflection. This phenomenon is known as reflection of light.

Question 9.
Define the following:
1. Reflected Ray
2. Angle of reflection.
1. Reflected Ray. A streak of light, starting from the mirror, is called reflected ray.

2. Angle of reflection. The angle made by the reflected ray with the normal at the point of incidence is called angle of reflection. It is represented by r.

Question 10.
If incident ray strikes the mirror at 90°, what will be the angle of reflection ?
If incident ray strikes the mirror normally, then after reflection, the ray will come back along the same path. As the angle of incidence is zero, so angle of reflection will also be zero.

Question 11.
Define the term ‘Dispersion of light.’
Dispersion of Light.
When a beam of light passes through a prism, the white light splits into seven colours. This phenomenon of splitting of white light into its constituent colours by a prism is known as dispersion of light.

Question 12.
While passing through a prism, why does the white light split into seven colours.
The rays of different colours pass smoothly through air but when passing through a prism they have to change the speed according to the angle of prism. Different colours have different wave lengths and thus, they choose different paths. So, the spectrum is seen.

Question 13.
What is myopia ?
Myopia.
The focal length of the eyes of some people is very small. Therefore, the image of distant object is not formed on their retina but it is formed at a point in front of the retina. In other words, they cannot see distant objects. This defect of vision is called Myopia or short sightedness.

Question 14.
What is hypermetropia ?
Hypermetropia.
When people grow old, the muscles of the eyes lose their strength to control the curvature of the lens. As a result, the image of nearby objects is not formed at the retina, but it is formed behind the retina. So these people cannot see nearby objects clearly. This defect of vision is called Hypermetropia or Farsightedness.

Question 15.
Explain in short perception of colour.
Perception of colour.
Human eye contains large number of rods and cones which are sensitive to light. Rods respond to the intensity of light and cones respond to the colour of the light. If cone cells are absent in the eye then such a person is colour blind. With the help of cones cells one can perceive colour. This is called perception of colour.

Question 16.
The following picture shows the reflection of light:

(A) Name the ray AO
(B) Name the ray OB
(C) Find the value of angle x
(A) Name of ray AO = Incident7 ray
(B) Name the ray OB = Reflected ray
(C) Value of angle x = 30° because angle of incidence is equal to angle of reflection.

Question 1.
Differentiate between a real image and a virtual image.
Differences between a real image and a virtual image.

 Real Image Virtual Image 1. The real image is formed when the rays of light actually meet after reflection. 1. The image formed is virtual when the rays of light don’t meet after reflection. 2. Real image can be obtained on the screen. 2. Virtual image cannot be obtained on the screen. 3. Real image is always inverted. 3. Virtual image is always erect.

Question 2.
State the characteristics of image formed by a plane mirror.
Characteristics of image formed in a plane mirror.

1. The image is as far behind the plane mirror, as the object is in front of it.
2. The image is laterally (sideways) inverted.
3. The image is of the same size as that of the object.
4. The image formed in a plane mirror is virtual, erect and of the same size as the object.
5. The image formed in a plane mirror cannot be obtained on the screen.

Light PSEB 8th Class Science Notes

• Light is a form of energy.
• Light travels in a straight line.
• Light enables us to see the objects around us.
• Light reflected from the objects falls into our eyes and thus, we can see the objects.
• Those objects, which emit their own light, are called luminous objects.
• The objects, which do not emit light of their own, but they reflect light falling on them, are called non-luminous objects.
• Polished or shiny surfaces reflect light.
• A mirror changes the direction of light, that falls on it.
• Angle of incidence (∠i) is always equal to angle of reflection (∠r).
• Incident ray, normal at the point of incidence and reflected ray all lie in the same plane.
• Number of reflections can be achieved with the mirrors arranged at an angle.
• When the light passes through a prism, it undergoes dispersion and white light splits up into seven colours.
• The spectrum of sunlight consists of seven colours – Violet, Indigo, Blue, Green, Yellow, Orange and Red. These seven colours can be remembered by term VIBGYOR. Rainbow is a natural phenomenon of dispersion.
• Human eye is a sensitive organ, which enables us to see the objects around us.
• A human eye has a convex lens, whose focal length is adjusted by ciliary muscles. Reflections can be parallel or regular and diffused.
• Cones and rods are two types of nerve ending found in blind spot of the eye.
• Two types of resources for visually challenged persons are : Non-optical aids and optical aids.
• Braille system is one of the most important and popular resource , for visually challenged persons.
• Reflection of Light: The change in direction of light by a shiny surface is called reflection of light.
• Screen: The white sheet or surface on which, the image is obtained.
• Regular Reflection: Reflection taking place from a polished and regular surface.
• Scattering of Light: Diffusing of light in all directions.
• Diffused Reflection: The light rays reflected from non-polished or irregular surface.
• Incident Ray: A ray of light from a source of light falling on a given surface.
• Kaleideoscope: An instrument based on multiple reflection used to create new designs.
• Mirror: A smooth and shiny surface.
• Normal: The perpendicular to the polished surface (mirror) at the point of incidence.
• Source of Light: An object which emits light.
• Real Image: The image formed, when incident rays after reflection actually meet at a point.
• Virtual Image: The image formed, when incident rays after reflection do not actually meet, but appear to meet at a point.
• Angle of Incidence: The angle between the incident ray and the normal.
• Angle of Reflection: The angle between the reflected ray and the normal.
• Power of Accommodation is the ability of the eye to focus the distant objects as well as the nearby objects, at the retina by changing the focal length or converging power of its lens.
• Least Distance of Distinct Vision is the minimum distance at which object must be placed so that a normal eye may see the object clearly without any strain on the eye. It is about 25 cm for normal eye.
• Myopia or Short-Sightedness means a person can see only nearby objects clearly, but cannot see distant objects. This defect is removed by using spectacles with concave lens.
• Hypermetropia or Long-sightedness: A person suffering from this defect can see distant objects clearly but cannot see nearby objects. The defect is removed by using spectacles fitted with convex lens.
• Persistence of Vision: Impression of an image on the retina lasts for 0.1 sec after the removal of the object. This effect is known as persistence of vision.
• Dispersion of Light is the splitting of white or some other light into its constituents.
• Perception of Colour: Human eye contains a large number of cell rods and cones which are sensitive to light. Rods respond to the intensity of light and cones respond to the colour of the light. If cone cells are absent in the eye, then such a person is colour blind.

Punjab State Board PSEB 8th Class Science Book Solutions Chapter 16 Light Textbook Exercise Questions and Answers.

## PSEB Solutions for Class 12 Computer Science Chapter 1 Physical Fitness

Physical Education Guide for Class 12 PSEB Physical Fitness Textbook Questions and Answers

Question 1.
How many types of strength are there? Name them.
There are two types of strength:

• Dynamic strength
• Static strength.

Question 2.
How many components of Physical fitness are there? Name them.

• Strength
• Endurance
• Speed
• Flexibility
• Agibity
• Coordinaiton ability

Question 3.
Name short term races.
100mt., 200 mt., 400 mt., 4 x 100 m Relay, 4 x 200 mt. Relay, 110 mt hurdle, 100 mt hurdle.

Question 4.
Which type of flexibility is more Active flexibility or Passive flexibility?
Passive flexibility is more than active flexibility.

Question 5.
What is medium term endurance?
It can be required for such activities which lasts from 2 to 10 min. Middle term endurance depends on muscle endurance and speed endurance Middle distance races are the example of the middle term endurance (800 mt., 1500 m) etc.

Question 6.
What do you know about long term endurance?
It depends upon the aerobic energy system. Long term endurance can be developed for such an event which lasts for 10 min or more. Marathon, 5000 m and 10,000 m races are the examples of the long term endurance.

Question 7.
What do you know about passive flexibility?
It is the ability to perform extension movements around joints with wider range and some external helps. For example, stretching exercise with the help of a partner. This flexibility is more than active flexibility.

Question 8.
What are the different types of Endurance? Explain each of them in detail.
As per the requirements following are the categories of endurance
1. As per the Nature of the Activity:
(a) Basic Endurance:
Basic endurance mainly depends upon aerobic endurance. It is done in slow pace where all the muscle groups of the body are involved in a particular movement. Running, jogging, walking and swimming are the examples of basic endurance.

(b) General Endurance:
It depends upon both aerobic and anaerobic activities. It, is done in both slow and fast pace activities. This enables sportsperson to work for longer duration without any tiredness.

(c) Specific Endurance:
Specific endurance can be differ from sports to sports. Every sport has their own intensity. For example, marathon runners have to run long hours beside boxers have to complete their bout in 3 minute round.

2. As per the Duration of the Activity:
(a) Short Term Duration:
Exercises for short distance can be fixed with the rest interval of short duration. It lasts upto 2 minutes and also called anaerobic activities. Short term endurance is required to resist fatigue in sports activities such as sprints and middle distance races.

(b) Middle Term Endurance:
It can be required for such activities which lasts from 2 to 10 min. Middle term endurance depends on muscle endurance and speed endurance Middle distance races are the example of the middle term endurance (800 mt., 1500 m) etc.

(c) Long Term Endurance:
It depends upon the aerobic energy system. Long term endurance can be developed for such an event which lasts for 10 min or more. Marathon, 5000 m and 10,000 m races are the examples of the long term endurance.

Question 9.
Write a note on each of the following:
(i) speed
(ii) flexibility
(iii) co-ordinative ability.
(i) Speed:
Speed is maximum rate at which a person is able to move his body over a specific distance. We can say that speed is the ability to move from one place to another in the shortest possible time. This ability is mainly hereditary in nature. That is why we can improve speed after rigorous training upto 20% only. It is also said that sprinters are bom not made.

Types of Speed:
1. Reaction Speed: It is the ability to give a quick reaction on a signal. The sportsperson respond against the situation demand.

2. Acceleration Speed:
It is the ability to achieve maximum speed from stationary position. We can see it in sprints. Indirectly .this ability depends on the other factors like explosive strength, technique and flexibility.

3. Movement Speed:
It is the ability to do maximum movement in minimum time. These can be seen in team games, combative sports, racket sports, throws and gymnastics etc.

4. Locomotor Ability:
This is the ability to maintain the speed after accelerated maximally. This can be seen in few events such as short distance races, i.e. 100 m, 200 m and 400 m etc.

5. Speed Endurance:
It is the ability to maintain near maximal speed for a longer duration.

(ii) Flexibility:
Flexibility is the range of movement possible around a joint. In general terms, flexibility has been defined as the range of motion around a joint and its surrounding muscles during passive movements.

Types of Flexibility:
1. Static Flexibility:
It is the ability to extend various joints in a stationary position.
(a) Passive Flexibility:
It is the ability to perform extension movements around joints with wider range and some external helps. For example, stretching exercise with the ‘ help of a partner. This flexibility is more than active flexibility.

(b) Active Flexibility:
It is the ability to perform flexibility or extension movements with larger amplitude without any external help or a partner. For example, swinging of legs.

2. Dynamic Flexibility:
It is the ability to perform extension movements around joints with greater amplitude when the body is in motion. Dynamic flexibility is more specific to sports to sports movements. For example, running and somersault in gymanastics or diving in swimming etc.

(iii) Coordination Ability:
Coordination Ability is the ability to perform smooth and accurate motor task, often involving the use of the sense organs and series of correlated muscular contraction that affect a range of joint and therefore relative limb and body position. It depends on the neuro-muscular coordination of the body.

Types of Coordination Ability:
There are mainly seven types of coordinative abilities considered in sports. These are as follows:
1. Orientation Ability:
It is the ability of an individual to analyze and change his body position and its parts in time and space in relation to performance required. For example, gymnast changes his body position as per the requirements of sports performance and basket ball player changes his position from offense to defence as the ball possession goes to opponent.

2. Coupling Ability:
It is the ability of an individual to systematically and meaningfully combine the movement of different body parts for successful performance of sports movement. For example, during spiking in volleyball, the player jumps and hits the ball.

3. Differentiation Ability:
It is the ability which enables the sportsman to separate the different body position and its parts during execution of motor action with high accuracy and movement economy. For example, in volley ball when player jumps for spiking, but drops ball according to the situation.

4. Reaction Ability:
It is the ability of an individual to respond quickly to a given signal and perform the movement in well directed manner. For example, in 100 m sprint when an athlete gets the signal he reacts quickly and performs the movement in desired direction.

5. Balance Ability:
It is the ability of an individual to maintain the dynamic condition. For example, in 400 m race, runner should run in his own lane.

6. Rhythm Ability:
It is the ability of an individual to understand the rhythm of movement and to execute the movement with required rhythm. For example, taking lay-up shot in basketball.

It is the ability of an individual to bring about an effective change in the movement according to anticipated change in the situation. For example, adaptation of scoop to the hitting a ball in hockey.

Question 10.
What do you know about the importance of Physical fitness? Explain in detail.
People who are physically fit are able to enjoy their life to the fullest. In today’s scenario of technological development people hardly spend time for their physical fitness. Now, question arises why it is important to be physically fit. The answer lies in the following points:

1. Improves Overall Health:
Physically fit persons possess numerous health advantages such as respiratory, cardiovascular health and overall functioning of the body remain in active state. This helps, in reducing the chances of type 2 diabetes, heart diseases, reduces risk of some cancer and lastly helps in maintaining good health and wellness.

2. Weight Management:
As we all know that the person with over weight or obese people are more prone to health related problems such as high BP, Ghotestrol level, diabetes etc. So, people who are living active lifestyle and physically fit are less likely to face these problems as they are able to control and manage their optimum weight with the help of regular exercise and stay fit.

3. Importance as a stress management:
Through the physical fitness and wellness programme, an individual become capable of managing stress, releiving stress and easily distracted from the daily stresses. Hence, this help in staying active and balanced in any stage of life. So, in order to maintain relaxed state of mind, a person should be physically fit.

4. Reduced risk of injuries:
Physical fitness prevents the chances of injuries in later stage. The reason for the same could be the increased muscle strength, bone density, flexibility and stability. It reduces the chances of injuries especially, as a person get older e.g. strong bones mean less likely to suffer bone injuries as later age.

5. Increases life expectancy:
Regular exercise and physical acitivity reduces the chances of health related diseases, which increases life expectancy and reduce the risk of premature mortality. It has been observed that people who are more active tend to be healtheir and tend to live longer.

6. Proper growth and development:
Through fitness and wellness programme children tend to grow and develop better. They are able to attain good shape, height, structure and optimum weight with the help of their physical fitness programme. So, physically fit person are in well balanced state of their physical structure as well.

7. Improves work efficiency:
The person who are physically fit are tend to perform well in every sphere of life such as work place, family peer group etc. Due to their active and balance state of body and mind their output at work place is more and they tend to enjoy social group with more zeal and excitement. Hence, helps in enjoying their life to the fullest.

Hence, it can be concluded that physical fitness is important for the ‘‘Sound mind in a sound body”. To enjoy at every stage of life.

Question 11.
Write the meaning and definition of Physical fitness.
Physical fitness is one of the basic requirements of life. It is the ability to carry out our daily tasks without undue fatigue. It is also refer to balanced state of psychological, physiological or anatomical aspects of the person. The concept of physical fitness, in the field of physical education and sports, means the capability of an individual to meet the varied physical and physiological demands made by a sporting activity, without reducing the person to an excessively fatigued state. Such a state would be one in which individual can no longer perform the skills of the activity accurately and successfully.

It is necessary for every individual to be physically fit to perform their daily work with ease or without undue fatigue and to take part in various activities effectively. Everyone should be fit enough through participation in physical activities to develop the different components related to physical fitness.

1. According to Clarke:
“Physical fitness is the ability to carry out daily task with vigour and alertness without undue fatigue and ample energy to enjoy leisure time pursuits and to meet unforeseen emergencies.”

2. According to Bucher and Prentice:
“Physical fitness is organic development, muscular strength and stamina. Physical fitness implies efficient performance in exercises.”

3. According to Thomas: “Physical fitness is the total fundamental capacity of an individual to perform a given task”.

4. According to Mathews: “Physical fitness is the capacity of an individual to perform given physical tasks involving muscular effort”.

5. According to William: “Physical fitness is the capacity of an individual to perform physical work”.

6. According to Hubert Dhanaraj: “Physical fitness refers to the ability of the body to tolerate stress in all its kinds and maintain manifestations”.

7. According David R. Lamb: “Physical fitness is the capacity to meet the present and potential physical challenges of life with success.”

8. According to Web Encyclopaedia: ‘‘It is the ability of a person to do daily routine work without fatigue; moreover to participate in playful activity and still reserves enough capacity to meet any emergency.”

Hence, it is important for everyone to stay fit and healthy to perform his daily routine work effectively, to enjoy his life to fullest.

Question 12.
Explain the factors affecting Physical fitness in detail.
There are enormous factors which affects physical fitness in certain ways. Due to inactivity, both short term and long term physical fitness get affected in number of ways. These factors which affect physical fitness are as below:
1. Anatomical Structure:
Anatomical/body structure of every individual is different or they have different shape and sizes. Inappropriate shape and size always hinder in physical performance. Sometimes, genetic impaired organ limits the physical performance of an individual, e.g. a person with smaller lower limbs have more balance as compare to vice-versa.

2. Physiological Structure:
Our all internal system like respiratory system, circulatory system, muscular system and other body systems must work efficiently. Any malfunctioning in systems can affect the physical performance of an individual Example would be problem in breathing or heart diseases etc. may affect the endurance capacity of a person. Hence, for the optimal physical fitness an individual must be physiologically fit also.

3. Psychological Factor:
There are so many psychological disorders which has affect on physical performance e.g. stress, tension, anxiety etc. which are big barriers in performance. Mentally strong and stress free individual can be fit for sports. Stress and tension always limits the physical fitness of a person and hence, affects the performance.

4. Heredity and Environment:
Both, heredity and environment affects physical fitness of an individual. Heredity and environment interacts to produce their effects. This means that the way genes act depends on the environment in which they act. e.g. if any person is a good sportsman, the child tend to have some traits of physical domain. Similarly, environmental variables also effects an individual e.g. difference of height in Japanese and AmericAnswer:

5. Good Posture:
Postural deformities always creates hinderance in physical fitness, for example muscle imbalance, pain, nutrition deficiency, lordosis, scoliosis, round shoulder, knock knees etc. can affect physical fitness of a person, e.g. A person with flat feet would not be able to perform better in events demanding speed.

6. Diet:
Diet plays a major role in physical performance and it is required to maintain physical fitness level. Right amount of calories and nutrition will help athlete to perform their best. Without adequate carbohydrate and fluid, an athlete gets tired very easily and quickly. Protein is needed to rebuild muscles. Without carbohydrates, protein, vitamins athlete will not perform well and it also decreases physical fitness.

7. Life Style:
A person who follow good life style are more fit and perform better in physical performance. Life style does not mean luxuries living; it means living with good habits. An individual who is habitual of smoking, liquor, drug etc. cannot perform well on these components of physical fitness. It affects physical fitness and overall health of a person.

8. Climate:
Different climatic conditions always affects the physical fitness of a person. There are different climatic conditions like winter, summer, humid etc. which influence physical fitness. For better physical performance one must trained themselves in different climate conditions. For example if an individual belongs to the hot and humid area and they have to compete in cold area then, it affects their physical performance. To avoid these barriers one must practice in different climates.

9. Inactivity:
Lack of physical activity leads individual towards sedentary life style which also creates malfunctioning in body system. Physical activity is the term used to describe any kind of everyday activity where body’s movement bums calories. Example would be walking, running, cycling, swimming, sweeping or other household work. Due to inactivity body system gets weaken and other health issues arises.

10. Injury:
Injuries are part of sports. Lack of injury management can decrease performance as well as it affects psychologically on athletes’ mind. Severe or long term injuries often affecting more mentally then physically. Long term injuries leads to inactivity which ultimately affects the physical fitness of a person.

11. Age:
Age differences always affects physical fitness of an individual. As we cannot compare the physical efficiency of an adult with younger ones. In the same way when we grow older, our muscle mass decreases and body fat increases which really affects physical fitness.

12. Gender:
Gender plays a major role in physical performance. Both male and female have huge structural differences. For example female bodies are less muscular, but their joints are more flexible, which gives them greater range of motion and they have an advantage in sports such as gymnastics. Men have larger skeletal muscles as well as larger heart, which generate more power, strength, speed and endurance.

13. Healthy environment:
A healthy environment at school, home or at playfield is helpful in better physical health and fitness. It also encourages athlete to get best physical performance. A healthy environment and good participation is essential for proper rowth and development which plays a key role in physical fitness.

PSEB 12th Class Physical Education Guide Physical Fitness Important Questions and Answers

Question 1.
Enlist any two types of speed.
Reaction Speed, Acceleration Speed.

Question 2.
In how many types endurance can be divided?
Two types.

Question 3.
Give various types of strength.
(i) Dynamic Strength
(ii) Static Strength.

Question 4.
At what age weight training programme should be started?
At the age of 18 years.

Question 5.
Enlist any two importance of physical fitness.
(i) Improves overall health.
(ii) Weight management.

Question 6.
Give various components of physical fitness.
Strength, Speed, Flexibility, Agility, Balance and Coordination ability.

Question 7.
What is the other name for dynamic strength?
Isotonic Strength.

Question 8.
Give substitute name for static strength.
Isometric Strength.

Question 9.
What is balance?
The ability to control the body position, either stationary or in movement is termed as balance.

Question 10.
Name various types of flexibility.
(i) Static flexibility.
(ii) Dynamic flexibility.

Question 11.
Enlist any two coordination abilities.
(i) Orientation ability
(ii) Coupling Ability

Question 12.
Give any two methods for developing agility.

• Shuttle Run

Question 13.
How does William express his views about physical fitness?
According to William, “Physical fitness is the capacity of an individual to perform physical work”.

Question 14.
What is strength?
The extent to which muscles can exert force by contracting against resistance is known to be strength. In simple words its an ability to work against resistance.

Question 15.
Define strength in the words of Muller.
According to Muller,” Strength may be defined as “The force, a muscle can exert against a resistance in one maximal effort”. It is measured in units of pounds or kilograms.”

Question 16.
How does Mathews define strength?
According to Mathews,” Muscular Strength is the force that a muscle or group of muscles can exert against a resistance in one maximum effort.”

Question 17.
What is static strength?
It is the ability of muscles to act against resistance without changing or shortening the length, e.g. Pushing against wall in which muscles develops tension without changing its length.

Question 18.
It is the combination of speed and strength. It is the ability to overcome resistance with high speed. Explosive strength can be seen in sprint races, weight lifting, hammer throw, long jump and high jump etc.

Question 19.
It is the combination of strength and endurance. It is the ability to overcome resistance for a longer duration. Long distance races, swimming and cycling are the examples of strength endurance.

Question 20.
Whether the muscle changes its length in static strength?
No.

Question 21.
What is basic endurance?
Basic endurance mainly depends upon aerobic endurance. It is done in slow pace where all the muscle groups of the body are involved in a particular movement. Running, jogging, walking and swimming are the examples of basic endurance.

Question 22.
What is general endurance?
It depends upon both aerobic and anaerobic activities. It is done in both slow and fast pace activities. This enables sportsperson to work for longer duration without any tiredness.

Question 23.
General endurance is part of which type of endurance.
Nature of the activity.

Question 24.
If a boxer has to complete for three minutes boxing round, then which type of endurance is required?
Specific endurance.

Question 25.
What is the meaning of aerobic?
Aerobic means when the oxygen demand is meet during exercise and practice.

Question 26.
Explain middle term endurance in your own words.
It can be required for such activities which lasts from 2 to 10 min. Middle term endurance depends on muscle endurance and speed endurance Middle distance races are the example of the middle term endurance (800 m, 1500 m) etc.

Question 27.
In which type of races short term endurance is required?
100 mt., 200 mt., 400 mt. etc.

Question 28.
The activities which that end from 2 minutes 10 minutes, what type of endurance is required for these activities.
Middle term endurance.

Question 29.
Which type of endurance is required in 5000 and 10000 metre races?
Long term endurance.

Question 30.
Middle term of endurance is part of which types of endurance?
Endurance on the basis of duration of activity.

Question 31.
What percentage of speed can be improved after stermous training?
Upto 20%.

Question 32.
What do you mean by locomoter ability?
This is the ability to maintain the speed after accelerated maximally. This can be seen in few events such as short distance races, i.e. 100 m, 200 m and 400 m etc.

Question 33.
What is speed endurance?
It is the ability to maintain near maximal speed for a longer duration.

Question 34.
Which component of physical fitness is improved with shuttle run, polymetric jump and tuck jumps.
Agility.

Question 35.
It is the ability of an individual to bring about an effective change in the movement according to anticipated change in the situation. For example, adaptation of scoop to the hitting a ball in hockey.

Question 1.
Define physical fitness.
According to Bucher and Prentice, “Physical fitness is organic development, muscular strength and stamina. Physical fitness implies efficient performance in exercises.”

Question 2.
Give any two importance of physical fitness.
1. Improves Overall Health:
Physically fit persons possess numerous health advantages such as respiratory, cardiovascular health and overall functioning of the body remain in active state. This helps in reducing the chances of type 2 diabetes, heart diseases, reduces risk of some cancer and lastly helps in maintaining good health and wellness.

2. Weight Management:
As we all know that the person with over weight or obese people are more prone to health related problems such as high BP, Chotestrol level, diabetes etc. So, people who are living active lifestyle and physically fit are less likely to face these problems as they are able to control and manage their optimum weight with the help of regular exercise and stay fit.

Question 3.
Define Endurance.
According to Barrow and McGee, “Endurance is the result of a physiological capacity of the individual to sustain movement over a period of time”.

Question 4.
What do you mean by explosive strength?
It is the combination of speed and strength. It is the ability to overcome resistance with high speed. Explosive strength can be seen in sprint races, weight lifting, hammer throw, long jump and high jump etc.

Question 5.
Enlist various factors affecting physical fitness.

• Anatomical Structure
• Physiological Structure
• Psychological Factor
• Heredity and Environment

Question 6.
Define Speed.
According to Johnson and Nelson, “speed is the rate at which a person can propel his body or parts of his body through space”.

Question 7.
What do you mean by strength endurance?
It is the combination of strength and endurance. It is the ability to overcome resistance for a longer duration. Long distance races, swimming and cycling are the examples of strength endurance.

Question 8.
Enlist two factors affecting physical fitness.
Psychological Factor:
There are so many psychological disorders which has affect on physical performance e.g. stress, tension, anxiety etc. which are big barriers in performance. Mentally strong and stress free individual can be fit for sports. Stress and tension always limits the physical fitness of a person and hence, affects the performance.

Diet:
Diet plays a major role in physical performance and it is required to maintain physical fitness level. Right amount of calories and nutrition will help athlete to perform their best. Without adequate carbohydrate and fluid, an athlete gets tired very easily and quickly. Protein is needed to rebuild muscles. Without carbohydrates, protein, vitamins athlete will not perform well and it also decreases physical fitness.

Question 9.
What points should be taken into consideration while perparing fitness programme?
Age:
Age differences always affects physical fitness of an individual. As we cannot compare the physical efficiency of an adult with younger ones. In the same way when we grow older, our muscle mass decreases and body fat increases which really affects physical fitness.

Gender:
Gender plays a major role in physical performance. Both male and female have huge structural differences. For example female bodies are less muscular, but their joints are more flexible, which gives them greater range of motion and they have an advantage in sports such as gymnastics. Men have larger skeletal muscles as well as larger heart, which generate more power, strength, speed and endurance.

Question 10.
What is the meaning of strength endurance?
It is the combination of strength and endurance. It is the ability to overcome resistance for a longer duration. Long distance races, swimming and cycling are the examples of strength endurance.

Question 11.
What do you understand by speed and strength?
Speed: Speed is maximum rate at which a person is able to move his body over a specific distance.
Strength. It is defined as the force exerted by muscles during a single maximal muscular contraction.

Question 12.
What are the factors affecting physical fitness?
1. Anatomical Structure:
Anatomical/body structure of every individual is different or they have different shape and sizes. Inappropriate shape and size always hinder in physical performance. Sometimes, genetic impaired organ limits the physical performance of an individual, e.g. a person with smaller lower limbs have more balance as compare to vice-versa.

2. Psychological Factor:
There are so many psychological disorders which has affect on physical performance e.g. stress, tension, anxiety etc. which are big barriers in performance. Mentally strong and stress free individual can be fit for sports. Stress and tension always limits the physical fitness of a person and hence, affects the performance.

Question 13.
Define reaction speed.
It is the ability to give a quick reaction on a signal. The sportsperson respond against the situation demand.

Question 14.
What is agility?
The ability to perform a series of explosive movements in rapid succession in opposing directions (zig-zag running shuttle run or cutting movement). In other words, it can be termed as how quickly a person respond to a given stimulus.

Question 15.
Give any one definition of physical fitness.
According David R. Lamb, “Physical fitness is the capacity to meet the present and potential physical challenges of life with success.”

Question 16.
Enlist any two elements of physical fitness.
Strength:
The extent to which muscles can exert force by contracting against resistance is known to be strength. In simple words its and ability to work against resistance.

Agility: It is the ability to move and change direction and position of the body quickly and effectively while under control.

Question 17.
Elaborate the term anatomical structure.
Anatomical/body structure of every individual is different or they have different shape and sizes. Inappropriate shape and size always hinder in physical performance. Sometimes, genetic impaired organ limits the physical performance of an individual, e.g. a person with smaller lower limbs have more balance as compare to vice-versa.

Question 18.
Does injuries affects physical fitness and why?
Yes, because injuries are part of sports. Lack of injury management can decrease performance as well as it affects psychologically on athletes’ mind. Severe or long term injuries often affecting more mentally then physically. Long term injuries leads to inactivity which ultimately affects the physical fitness of a person.

Question 19.
How does healthy environment affects the physical fitness of a person?
A healthy environment at school, home or at playfield is helpful in better physical health and fitness. It also encourages athlete to get best physical performance. A healthy environment and good participation is essential for proper growth and development which plays a key role in physical fitness.

Question 20.
Explain about general endurance and middle term endurance.
General Endurance:
It depends upon both aerobic and anaerobic activities. It is done in both slow and fast pace activities. This enables sportsperson to work for longer duration without any tiredness.

Middle Term Endurance:
It can be required for such activities which lasts from 2 to 10 min. Middle term endurance depends on muscle endurance and speed endurance Middle distance races are the example of the middle term endurance (800 m, 1500 m) etc.

Question 21.
What is the difference between reaction speed and movement speed?
Reaction Speed:
It is the ability to give a quick reaction on a signal. The sportsperson respond against the situation demand.

Movement Speed:
It is the ability to do maximum movement in minimum time. These can be seen in team games, combative sports, racket sports, throws and gymnastics etc.

Question 22.
Locomotor speed:
This is the ability to maintain the speed after accelerated maximally. This can be seen in few events such as short distance races, i.e. 100 m, 200 m and 400 m etc.

Acceleration Speed:
It is the ability to achieve maximum speed from stationary position. We can see it in sprints. Indirectly ,this ability depends on the other factors like explosive strength, technique and flexibility.

Question 1.
Differentiate between Isotonic and Isometric strength.
Dynamic Strength or Isotonic Strength:
When the contraction results in the change of muscles length and the pressure remains same throughout the contraction, it can be called dynamic strength. For example, involving movement at more than one joint i.e. push ups, pull-ups, barbell press, squats, lunges and dead lifts etc. Dynamic strength can also be divided in three parts:

Static strength or Isometric strength:
It is the ability of muscles to act against resistance without changing or shortening the length, e.g. Pushing against wall in which muscles develops tension without changing its length.

Question 2.
How would you classify endurance on the basis of nature of activity?
1. Basic Endurance:
Basic endurance mainly depends upon aerobic endurance. It is done in slow pace where all the muscle groups of the body are involved in a particular movement. Running, jogging, walking and swimming are the examples of basic endurance.

2. General Endurance:
It depends upon both aerobic and anaerobic activities. It is done in both slow and fast pace activities. This enables sportsperson to work for longer duration without any tiredness.

3. Specific Endurance:
Specific endurance can be differ from sports to sports. Every sport has their own intensity. For example, marathon runners have to run long hours beside boxers have to complete their bout in 3 minute round.

Question 3.
Elucidate the term short term endurance and middle term endurance.
1. Short Term Endurance:
Exercises for short distance can be fixed with the rest interval of short duration. It lasts upto 2 minutes and also called anaerobic activities. Short term endurance is required to resist fatigue in sports activities such as sprints and middle distance races.

2. Middle Term Endurance:
It can be required for such activities which lasts from 2 to 10 min. Middle term endurance depends on muscle endurance and speed endurance Middle distance races are the example of the middle term endurance (800 m, 1500 m) etc.

Question 4.
What do you know about coordination ability?
Coordination ability is the ability to perform smooth and accurate motor task, often involving the use of the sense organs and series of correlated muscular contraction that affect a range of joint and therefore relative limb and body position. It depends on the neuro¬muscular coordination of the body. The various elements of coordinative abilities are orientation ability, coupling, ability differentiation ability, reaction ability, balance ability, rhythm, ability and adaptation ability.

Question 5.
Differentiate between agility and speed.
Speed is maximum rate at which a person is able to move his body over a specific distance. We can say that speed is the ability to move from one place to another in the shortest possible time.

Agility is the ability to move and change direction and position of the body quickly and effectively while under control. It requires quick reflexes, coordination, balance, speed, and correct response to the changing situation.

Question 6.
Briefly explain about the types of strength.
As per the requirements in different sports settings the following classifications of the strength can be given:
1. Dynamic strength or isotonic strength
2. Static strength or isometric strength

1. Dynamic Strength or Isotonic Strength:
When the contraction results in the change of muscles length and the pressure remains same throughout the contraction, it can be called dynamic strength. For example, involving movement at more than one joint i.e. push ups, pull- ups, barbell press, squats, lunges and dead lifts etc. Dynamic strength can also be divided in three parts:

(a) Maximum Strength:
It is the greatest strength that can be achieved voluntarily against a resistance. We can also define maximum strength as the amount of muscuo skeletal force a person can generate with all-out efforts..

(b) Explosive Strength:
It is the combination of speed and strength. It is the ability to overcome resistance with high speed. Explosive strength can be seen in sprint races, weight lifting, hammer throw, long jump and high jump etc.

(c) Strength endurance:
It is the combination of strength and endurance. It is the ability to overcome resistance for a longer duration. Long distance races, swimming and cycling are the examples of strength endurance.

2. Static strength or Isometric strength:
It is the ability of muscles to act against resistance without changing or shortening the length, e.g. Pushing against wall in which muscles develops tension without changing its length.

Question 7.
What do you know about flexibility? Give its types also.
Flexibility is the range of movement possible around a joint. In general terms, flexibility has been defined as the range of motion around a joint and its surrounding muscles during passive movements.

Types of Flexibility
1. Static Flexibility: It is the ability to extend various joints in a stationary position.
(a) Passive Flexibility:
It is the ability to perform extension movements around joints with wider range and some external helps. For example, stretching exercise with the help of a partner.

(b) Active Flexibility:
It is the ability to perform flexibility or extension movements with larger amplitude without any external help or a partner. For example, swinging of legs.

2. Dynamic Flexibility:
It is the ability to perform extension movements around joints with greater amplitude when the body is in motion. Dynamic flexibility is more specific to sports to sports movements. For example, running and somersault in gymanastics or diving in swimming etc.

Question 8.
Enlist various types of speed.
1. Reaction Speed: It is the ability to give a quick reaction on a signal. The sportsperson respond against the situation demand.

2. Acceleration Speed:
It is the ability to achieve maximum speed from stationary position. We can see it in sprints. Indirectly ,this ability depends on the other factors like explosive strength, technique and flexibility.

3. Movement Speed:
It is the ability to do maximum movement in minimum time. These can be seen in team games, combative sports, racket sports, throws and gymnastics etc.

4. Locomotor Ability:
This is the ability to maintain the speed after accelerated maximally. This can be seen in few events only i.e. 100 m, 200 m and 400 m etc.

5. Speed Endurance: It is the ability to maintain near maximal speed for a longer duration.

Question 9.
Highlight any three factors affecting physical fitness.
1. Life Style:
A person who follow good life style are more fit and perform better in physical performance. Life style does not mean luxuries living; it means living with good habits. An individual who is habitual of smoking, liquor, drug etc. cannot perform well on these components of physical fitness. It affects physical fitness and overall health of a person.

2. Good Posture:
Postural deformities always creates hindrance in physical fitness, for example muscle imbalance, pain, nutrition deficiency, lordosis, scoliosis, round shoulder, knock knees etc. can affect physical fitness of a person, e.g. A person with flat feet would not be able to perform better in events demanding speed.

3. Diet:
Diet plays a major role in physical performance and it is required to maintain physical fitness level. Right amount of calories and nutrition will help athlete to perform their best. Without adequate carbohydrate and fluid, an athlete gets tired very easily and quickly. Protein is needed to rebuild muscles. Without carbohydrates, protein, vitamins athlete will not perform well and it also decreases physical fitness.

Question 10.
Differentiate between locomotor ability and reaction ability?
Reaction Ability.
It is the ability of an individual to respond quickly to a given signal and perform the movement in well directed maimer. For example, in 100 m sprint when an athlete gets the signal he reacts quickly and performs the movement in desired direction.

Locomotor Ability:
This is the ability to maintain the speed after accelerated maximally. This can be seen in few events such as short distance races, i.e. 100 m, 200 m and 400 m etc.

Question 1.
Write the basic components of physical fitness strength and speed.
Strength is defined as the force exerted by muscles groups during a single maximal muscle contraction. Strength can be developed with the right kind and amount of training.

Types of Strength
As per the requirements in different sports settings the following classifications of the strength can be given:
1. Dynamic strength or isotonic strength
2. Static strength or isometric strength

1. Dynamic Strength or Isotonic Strength:
When the contraction results in the change of muscles length and the pressure remains same throughout the contraction, it can be called dynamic strength. For example, involving movement at more than one joint i.e. push ups, pull- ups, barbell press, squats, lunges and dead lifts etc. Dynamic strength can also be divided in three parts:

(a) Maximum Strength:
It is the greatest strength that can be achieved voluntarily against a resistance. We can also define maximum strength as the amount of muscuo skeletal force a person can generate with all-out efforts.

(b) Explosive Strength:
It is the combination of speed and strength. It is the ability to overcome resistance with high speed. Explosive strength can be seen in sprint races, weight lifting, hammer throw, long jump and high jump etc.

(c) Strength endurance:
It is the combination of strength and endurance. It is the ability to overcome resistance for a longer duration. Long distance races, swimming and cycling are the examples of strength endurance.

2. Static strength or Isometric strength:
It is the ability of muscles to act against resistance without changing or shortening the length, e.g. Pushing against wall in which muscles develops tension without changing its length.

Speed:
Speed is maximum rate at which a person is able to move his body over a specific distance. We can say that speed is the ability to move from one place to another in the shortest possible time.
According to Barrow and McGee, “speed is the capacity of an individual to perform successive movement of the same pattern at a fast rate”. According to Johnson and Nelson, “speed is the rate at which a person can propel his body or parts of his body through space”.
Speed comprises quick response, acceleration, maximum speed and speed endurance.

Types of Speed
1. Reaction Speed: It is the ability to give a quick reaction on a signal. The sportsperson respond against the situation demand.

2. Acceleration Speed:
It is the ability to achieve maximum speed from stationary position. We can see it in sprints. Indirectly ,this ability depends on the other factors like explosive strength, technique and flexibility.

3. Movement Speed:
It is the ability to do maximum movement in minimum time. These can be seen in team games, combative sports, racket sports, throws and gymnastics etc.

4. Locomotor Ability:
This is the ability to maintain the speed after accelerated maximally. This can be seen in few events only i.e. 100 m, 200 m and 400 m etc.

5. Speed Endurance: It is thejability to maintain near maximal speed for longer duration.

Question 2.
Explain the importance of physical fitness.
People who are physically fit are able to enjoy their life to the fullest. In today’s scenario of technological development people hardly spend time for their physical fitness. Now, question arises why it is important to be physically fit. The answer lies in the following points:

1. Improves Overall Health:
Physically fit persons possess numerous health advantages such as respiratory, cardiovascular health and overall functioning of the body remain in active state. This helps in reducing the chances of type 2 diabetes, heart diseases, reduces risk of some cancer and lastly helps in maintaining good health and wellness.

2. Weight Management:
As we all know that the person with over weight or obese people are more prone to health related problems such as high BP, Chotestrol level, diabetes etc. So, people who are living active lifestyle and physically fit are less likely to face these problems as they are able to control and manage their optimum weight with the help of regular exercise and stay fit.

3. Importance as a stress management:
Through the physical fitness and wellness programme, an individual become capable of managing stress, releiving stress and easily distracted from the daily stresses. Hence, this help in staying active and balanced in any stage of life. So, in order to maintain relaxed state of mind, a person should be physically fit.

4. Reduced risk of Injuries:
Physical fitness prevents the chances of injuries in later stage. The reason for the same could be the increased muscle strength, bone density, flexibility and stability. It reduces the chances of injuries especially, as a person get older e.g. strong bones mean less likely to suffer bone injuries as later age.

5. Increases life expectancy:
Regular exercise and physical acitivity reduces the chances of health related diseases, which increases life expectancy and reduce the risk of premature mortality. It has been observed that people who are more active tend to be healtheir and tend to live longer.

6. Proper growth and development:
Through fitness and wellness programme children tend to grow and develop better. They are able to attain good shape, height, structure and optimun weight with the help of their physical fitness programme. So, physically fit person are in well balanced state of their physical structure as well.

7. Improves work efficiency:
The person who are physically fit are tend to perform well in every sphere of life such as work place, family peer group etc. Due to their active and balance state of body and mind their output at work place is more and they tend to enjoy social group with more zeal and excitement. Hence, helps in enjoying their life to the fullest.

Hence, it can be concluded that physical fitness is important for the “Sound mind in a sound body”. To enjoy at every stage of life.

Question 3.
Briefly explain the factors affecting physical fitness.
There are enormous factors which affects physical fitness in certain ways. Due to inactivity, both short term and long term physical fitness affected in number of ways. These factors which affect physical fitness are as ahead:

1. Anatomical Structure:
Anatomical/body structure of every individual is different or they have different shape and sizes. Inappropriate shape and size always hinder in physical performance. Sometimes, genetic impaired organ limits the physical performance of an individual, e.g. a person with smaller lower limbs have more balance as compare to vice-versa.

2. Physiological Structure:
Our all body system like respiratory system, circulatory system, muscular system and other body systems must work efficiently. Any malfunctioning in systems can affect the physical performance. Example would be problem in breathing or heart diseases etc. Hence, for the optimal physical fitness an individual must be physiological fit also.

3. Psychological Factor:
There are so many psychological disorders which has affect on physical performance e.g. stress, tension, anxiety etc. which are big barriers in performance. Mentally strong and stress free individual can be fit for sports. Stress and tension always limits the physical fitness of a person and hence, affects the performance.

4. Heredity and Environment:
Both, heredity and environment affects physical fitness of an individual. Heredity and environment interacts to produce their effects. This means that the way genes act depends on the environment in which they act. e.g. if any person is a good sportsman, the child tend to have some traits of physical domain. Similarly, environmental variables also effects an individual e.i., heighted Japanese and Americans.

5. Good Posture:
Postural deformities always creates hinderance in physical fitness, for example muscle imbalance, pain, nutrition deficiency, lordosis, scoliosis, round shoulder, knock knees etc. can affect physical fitness of a person, e.g. A person with flat feet would not be able to perform better in events demanding speed.

6. Diet:
Diet plays a major role in physical performance and it is required to maintain physical fitness level. Right amount of calories and nutrition will help athlete to perform their best. Without adequate carbohydrate and fluid, an athlete gets tired very easily and quickly. Protein is needed to rebuild muscles. Without carbohydrates, protein, vitamins athlete will not perform well and it also decreases physical fitness.

7. Life Style:
A person who follow good life style are more fit and perform better in physical performance. Life style does not mean luxuries living; it means living with good habits. An individual who is habitual of smoking, liquor, drug etc. cannot perform well on these components of physical fitness. It affects physical fitness and overall health of a person.

8. Climate:
Different climatic conditions always affects the physical fitness of a person. There are different climatic conditions like winter, summer, humid etc. which influence physical fitness. For better physical performance one must trained themselves in different climate conditions. For example if an individual belongs to the hot and humid area and they have to compete in cold area then, it affects their physical performance. To avoid these barriers one must practice in different climates.

9. Inactivity:
Lack of physical activity leads individual towards sedentary life style which also creates malfunctioning in body system. Physical activity is the term used to describe any kind of everyday activity where body’s movement bums calories. Example would be walking, running, cycling, swimming, sweeping or other household work. Due to inactivity body system gets weaken and other health issues arises.

10. Injury:
Injuries are part of sports. Lack of injury management can decrease performance as well as it affects psychologically on athletes mind. Severe or long term injuries often affecting more mentally then physically. Long term injuries leads to inactivity which ultimately affects the physical fitness of a person.

11. Age:
Age differences always affects physical fitness of an individual. As we cannot compare the physical efficiency of an adult with younger ones. In the same way when we grow older, our muscle mass decreases and body fat increases which really affects physical fitness.

12. Gender:
Gender plays a major role in physical performance. Both male and female have huge structural differences. For example female bodies are less muscular, but their joints are more flexible, which gives them greater range of motion and they have an advantage in sports such as gymnastics. Men have larger skeletal muscles as well as larger heart, which generate more power, strength, speed and endurance.

13. Healthy environment:
A healthy environment at school, home or at playfield is helpful in better physical health and fitness. It also encourages athlete to get best physical performance. A healthy environment and good participation is essential for proper growth and development which plays a key role in physical fitness.

Question 4.
Explain flexibility alongwith its various types?
Flexibility:
Flexibility is the range of movement possible around a joint. In general terms, flexibility has been defined as the range of motion around a joint and its surrounding muscles.

Types of Flexibility:
1. Static Flexibility:
It is the ability to extend various joints in a stationary position.

(а) Passive Flexibility:
It is the ability to perform extension movements around joints with wider range and some external helps. For example, stretching exercise with the help of a partner. This flexibility is more then active flexibility,

(b) Active Flexibility:
It is the ability to perform flexibility or extension movements with larger amplitude without any external help or a partner. For example, swinging of legs.

2. Dynamic Flexibility:
It is the ability to perform extension movements around joints with greater amplitude when the body is in motion. Dynamic flexibility is more specific to sports to sports movements. For example, running and somersault in gymanastics or diving in swimming etc.

Question 5.
What do you know about coordination ability? Also explain various types of coordination ability.
Coordinative ability is the ability to perform smooth and accurate motor task, often involving the use of the sense organs and series of correlated muscular contraction that affect a range of joint and therefore relative limb and body position. It depends on the neuromuscular coordination of the body.

Types of Coordinative Ability:
There are mainly seven types of coordinative abilities considered in sports. These are as follows:

1. Orientation Ability:
It is the ability of an individual to analyze and change his body position and its parts in time and space in relation to performance required. For example, gymnast changes his body position as per the requirements of sports performance and basket ball player changes his position from offense to defence as the ball possession goes to opponent.

2. Coupling Ability:
It is the ability of an individual to systematically and meaningfully combine the movement of different body parts for successful performance of sports movement. For example, during spiking in volleyball, the player jumps and hits the ball.

3. Differentiation Ability:
It is the ability which enables the sportsman to separate the different body position and its parts during execution of motor action with high accuracy and movement economy. For example, in volley ball when player jumps for spiking, but drops ball according to the situation.

4. Reaction Ability:
It is the ability of an individual to respond quickly to a given signal and perform the movement in well directed manner. For example, in 100 m sprint when an athlete gets the signal he reacts quickly and performs the movement in desired direction.

5. Balance Ability:
It is the ability of an individual to maintain the dynamic condition. For example, in 400 m race,, runner should run in his own lane.

6. Rhythm Ability:
It is the ability of an individual to understand the rhythm of movement and to execute the movement with required rhythm. For example, taking lay-up shot in basketball.

It is the ability of an individual to bring about an effective change in the movement according to anticipated change in the situation. For example, adaptation of scoop to the hitting a ball in hockey.

Physical Fitness PSEB 12th Class Physical Education Notes

The term Physical fitness has different notions for different segment of people. It not only refers to being physically fit but also refers to as balanced state of mind. A person can only be considered fit if he is able to function well without any undue fatigue or tiredness. A person who is fit both on physical and mental aspect stays strong in every sphere of life. Now, lets discuss the definition of physical fitness. It is the ability of an individual to work effectively and efficiently with joy and pleasure.

According to David R. Lamb, “Physical fitness is the capacity to meet the present and potential physical challenges of fife with success.” In order to achieve the optimum level of physical fitness one must possess basic components such as strength, speed, endurance, agility, flexibility and coordinative abilities. If a person is having these components, then he will be considered to be physically fit. But, there are various factors which may influence physical fitness of an individual such as anatomical structure, physiological and psychological make up, posture, diet, life style, inactivity, injury, age and gender etc. So, these factors are responsible to have major influence on the physical fitness of an individual.

Hence, physical fitness plays a vital role to live healthy, prosperous and conducive life in the present scenario of technological advancement. It helps in the proper growth and development with efficient functioning of physiological system in the body. These developments ultimately induce the feeling of balance state of mental health and physical health of a person

Punjab State Board PSEB 12th Class Physical Education Book Solutions Chapter 1 Physical Fitness Textbook Exercise Questions and Answers.

## PSEB 10th Class Welcome Life Guide | Welcome Life Guide for Class 10 PSEB in English Medium

Welcome Life Guide for Class 10 PSEB | PSEB 10th Class Welcome Life Book Solutions

Punjab State Board Syllabus PSEB 10th Class Welcome Life Book Solutions Guide Pdf in English Medium and Punjabi Medium are part of PSEB Solutions for Class 10.

## PSEB Solutions for Class 8 Science Chapter 15 Some Natural Phenomena

PSEB 8th Class Science Guide Some Natural Phenomena Textbook Questions and Answers

Exercises

Select the correct option in Question 1 and 2.

Question 1.
Which of following cannot be charged easily by friction ?
(a) A plastic scale
(b) A copper rod
(c) An inflated balloon
(d) A woollen cloth.
(b) A copper rod.

Question 2.
When a glass rod is rubbed with a piece of silk cloth the rod
(а) and cloth both acquire positive charge.
(b) becomes positively charged while the cloth has a negative charge.
(c) and the cloth both acquire negative charge.
(d) becomes negatively charged while the cloth is positive charged.
(b) becomes positively charged while the cloth has a negative charge.

Question 3.
Write T against true and F against false in the following statements.
[а] like charges attract each other.
False

[b] A charged glass rod attracts a charged plastic straw.
True

[c] Lightning conductor cannot protect a building from lightning.
False

[d] Earthquakes can be predicted in advance.
False

Question 4.
Sometimes, a crackling sound is heard while taking off sweater during winters. Explain.
Woollen clothes get electrically charged when they get rubbed. Due to rubbing attraction or repulsion occurs between their loose particles which results in crackling sound.

Question 5.
Explain why a charged body loses its charge if we touch it with our hand.
Human body is a conductor of electricity. When a body is touched with hand, the electric current of body passes to the earth through human body and body loses its charges.

Question 6.
Name the scale on which the destructive energy of an earthquakes is measured. An earthquake measures 3 on this scale. Would it be recorded by a seismograph ? Is it likely to cause much damage ?
Scale used to measure earthquake is Richter scale.
Earthquake with measure 3 can be recorded on seismograph but this earthquake is very feeble in its intensity and very less destructive.

Question 7.
Suggest three measures to protect ourselves from Lightning.
Or
Suggest any two safety measures that we should take to prevent damage caused by linghtning.
Measures of Protection:

1. On hearing thunder, go inside closed areas such as houses, buildings etc.
2. In bus, close all the doors and windows.
3. In open, sit on floor with your head in knees and arms.

Question 8.
Explain why a charged balloon is repelled by an other charged balloon whereas an uncharged balloon is attracted by another charged balloon ?
Same materials get same charges on rubbing and same charges repel each other.
Therefore, balloon on rubbing are similarly charged and thus repel each other while a charged and an uncharged balloon attract each other.

Question 9.
Describe with the help of a diagram an instrument which can be used to detect a charged body.

Electroscope is used to detect electric charges or kind of charge on a body.
To make an electroscope, take a glass jar. Cover it with a wooden or cardboard disc fixed with an aluminium foil on a paper clip in the vertical position.

Question 10.
List three states in India where earthquake are more likely to strike.
States of India, highly susceptible to earthquake:

1. Rann of Kutch
2. Rajasthan
3. Highlands of Sind-Ganga
4. Kashmir.

Question 11.
Suppose you are outside your home and an earthquake strikes. What precaution would you take to protect yourself ?
Protection against earthquake outside the house.

1. Lie down in open far from buildings, trees and electric wires.
2. Do not step out from car or bus.
3. Take car or bus towards open areas.

Question 12.
The weather department has predicted that a thunderstorm is likely to occur on a certain day. Suppose you have to go out on that day. Would you carry an umbrella ? Explain.
To go out during thunderstorm is not safe and with umbrella it is fatal because high buildings, electric wires, black materials etc. all attract thunderstorm. So, it is advisable to stay away from them.

PSEB Solutions for Class 8 Science Some Natural Phenomena Important Questions and Answers

Multiple Choice Questions

Question 1.
How many kinds of electric charge are there ?
(a) 2
(b) 3
(c) 4
(d) 6.
(a) 2.

Question 2.
The device used for testing electric charge is called:
(a) Electroscope
(b) Microscope
(c) Periscope
(d) Electroplating.
(a) Electroscope.

Question 3.
What is the measure of earthquake on Rictor scale that can cause devastation ?
(a) Less than 5
(b) Between 5 and 7
(c) Between 1 and 5
(d) More than 7.
(d) More than 7.

Question 4.
Opposite charges ………………. each other.
(а) Attract
(b) Repel
(c) Sometime attract sometime repel
(d) Neither attract nor repel.
(a) Attract.

Question 5.
The central region of earth is called:
(a) Inner core
(b) Outer core
(c) Mantle
(d) Earth crust.
(a) Inner core.

Question 6.
Which is the safest place to take shelter during lightning and thunderstorm ?
(a) Building
(b) Open area
(c) Under the tree
(d) All the above.
(a) Building.

Question 1.
What is amber ?
It is a type of resin.

Question 2.
What happens when amber is rubbed for longer time ?
A spark is produced.

Question 3.
Who established that spark and lightning were same thing ?
Benjamin Franklin, an American Scientist.

Question 4.
What happens when a plastic scale rubbed with dry hair is brought near pieces of paper ?
Scale attracts pieces of paper.

Question 5.
Give few examples of charged objects.

1. Plastic scale rubbed with hair.
2. Plastic refill rubbed with polythene.
3. Balloon rubbed with woollen cloth.

Question 6.
What happens when two balloons rubbed with woolen cloth are brought together.
They repel each other.

Question 7.
Which type of charges attract each other ?
Unlike or opposite charges attract each other.

Question 8.
How many types of charges are there ?
Two types of charges-

1. negative and
2. positive.

Question 9.
Why does a plastic comb rubbed in hair attract small bits of paper ?
Because it gets charged.

Question 10.
What will happen when two clouds with unlike charges approach each other ?
Lightning strikes.

Question 11.
Is human body a conductor or an insulator ?
A conductor.

Question 1.
Why is a balloon filled with air rubbed against hair, sticks to the wall when pressed against it ?
Air filled balloon when rubbed against hair gets, charged. The charged balloon then sticks to the wall, when pressed against it. It is because the charged balloon attracts the wall and holds on to it.

Question 2.
Why does the paper strip open up when touched with a charged rod ?
When we touch one side of the paper strip with a charged rod, the paper strip opens up. The reason for this is that the two sides of the strip get same type of charge from the charged rod and thus repel each other. With the result, the paper strip opens up (diverges).

Question 3.
Why are we advised not to be under a tree, if we are in the open during a thunderstorm ?
A highly charged cloud when comes near the tree can induce a powerful opposite charge on the top of tree. This can cause lightning between the cloud and the earth through the tree. It can damage tree and can cause fire.

Question 4.
Why are tall buildings provided with metallic rods, running from the top of building to the ground ?
A highly charged cloud can induce an opposite charge on the pointed ends of the metallic rod. When it passes by the tall building, the similar charge passes to the earth through the metallic rod. The lightning passes to the earth safely, without causing any damage to the building.

Question 5.
What do you mean when we say that a body is electrically charged or electrified ?
A body like plastic comb, pen, etc. when rubbed with another body gets the property of attracting small pieces of paper or a pith ball. Then, such a body is a called electrically charged or electrified.

Question 6.
Write a short note on Tsunami.
Tsunami. Tsunami are long and high waves, which rise under sea due to earthquakes. It is usually a high speed wave, which rise in sea. It is also known as harbour wave.

Examples.

1. In 1819 on Hawain islands.
2. In 2004.

Effects of Tsunami.

1. Loss of Lives.
2. Loss of Aquatic life.
3. Physical damage of human life and property.
4. Uprooting of plants on the banks of sea or in coastal regions.

Question 7.
Write down the uses of electroscope.
Uses of electroscope:

1. Electroscope is used to detect the presence of charge.
2. It is used to find the type of charge.
3. It is used to compare the charges.

Question 8.
What is electric discharging (lightning) ?
Electric discharging (Lighting).
The phenomenon of lightning is caused due to discharge through air. It occurs when the charge accumulated in the clouds exceeds a certain limit. When unlike charged clouds come closer to each other, the charges in air between them move with a great velocity. Due to this, an intense spark of lightning is seen moving in the air. This is known as electric discharging or lightning.

Question 9.
Write two examples of electric discharge which are used to ignite the fuel.
Examples of Electric discharges:

1. By sparkplug in scooter and car.
2. By electric gas lighter used to ignite the gas stove in kitchens.

Question 10.
What are natural phenomena ?
Natural Phenomena.
The phenomena which occur suddenly in nature are called natural phenomena. They cause severe damage to life and property to related areas and environment is also affected with human life.
Examples : Earthquake, landslides, food, drought, cyclones, eruption of volcanoes, tsunami, etc.

Question 11.
What are cyclones ? Write effects and reasons caused by it.
Cyclone.
Cyclone is a terrible storm which has a speed more than 119 km per hour.

Reasons.
When sea water evaporates in summer season, it rises up and condenses to form cloud. To get the space of upward moving air, air rushes speedily under it. There forms a cyclic motion nearby a centre or due to difference in temperature and pressure present above the hot sea water, cyclones are produced.

Effects.
Cyclones affect crops, health, ships, etc. Landslides and foods cause severe damage to mankind.

Question 1.
Give an experiment to show that when two bodies are rubbed together, they get oppositely charged.

Experiment.
Take a plastic scale. Wrap flannel at its one end. Rub this side with another plastic scale. Bring these two scales separately near bits of tissue paper. We observe that both scales show attraction toward the bits of tissue paper. This proves that both the scales get charged on rubbing.

Now suspend one scale from a stand and bring the other close to it. They get attracted. It shows that they have opposite charges. It is because opposite charges attract each other. Thus, we may conclude that when two bodies are rubbed together, they get oppositely charged.

Question 2.
What is lightning ?
Lightning.
The phenomenon of lightning is caused due to electric discharge through air. It occurs when the charge accumulated in the clouds exceeds a certain limit. In these conditions, the small region of positive charges in the lower part induces a negative charge on the ground below it. The large force of attraction between the opposite charges becomes sufficient to break down the insulation of air.

Once this happens, the entire positive charge in the lower parts of the clouds passes to the earth through a narrow gap in the air. The huge negative charge gets accumulated in the lower parts of the cloud then passes through this conducting path in a very short time. The air in this narrow gap gets heated by the electrical energy to such a high temperature that it appears as a flash of light, which we see as lightning.

Question 3.
What safety measures should we take to prevent damage caused by lightning ?
Precautions to be taken to provide protection against lightning.
The following precautions should be taken to protect ourselves against lightning:

1. We should not stand under trees, when lightning occurs and even during rain, when there are chances of lightning to strike.
2. We should put up lightning conductor on our buildings to protect our lives and property from damage.
3. We should switch off TV sets during lightning for TV antennas are more prone to lightning strikes.

Question 4.
Discuss the construction and working of a lightning conductor.

Lightning Conductor.
It is a pointed long metal rod fixed along side of a building. The lower end of this rod is hurried deep under the earth.

Working of a Lightning Conductor.
A lightning conductor protects the building from the destructive effect of the lightning in two ways:
1. During a thunderstorm, a charged cloud passes above the point of the lightning conductor.
If’the cloud is positively charged, it induces a negative charge on its upper end.

This end being pointed cannot retain this charge and sends into the atmosphere a wind on negatively charged particles which cancel some of the positive charge on the clouds. This reduces the potential of the cloud below the spark potential and as such no lightning discharge takes place between the building and the cloud.

2. If a discharge actually takes place, the lightning conductor provides an easy passage to the charge from the cloud to the earth. The building is thus, saved from the destructive effects of the lightning.

Question 5.
What are causes and impacts of earthquake ? Write precautions against earthquake.
Earthquake.
Quakes are vibrations created in the earth’s crust. These may arise suddenly.

Reason of earthquake.
Geographically our earth is made up of seven long tactonic plates. These plates move very slowly. But whenever these plates acquire high speeds, there is a disturbance on earth’s surface. These movements of earth’s surface cause buildings to fall, bridges, roads etc. get broken.

Impacts of earthquake.
Tsunami.

1. It is cause of Tsunami (a seismic sea wave)
2. Many buildings fall down.
3. Supply of basic amenities is disturbed.
4. It causes health hazard.

Precautions against earthquakes:

1. In highly seismic areas timber must be used in constructions of buildings instead of heavy materials like mud, stone, brick etc.
2. It is better if the cupboards and shelves are fixed to the walls, so that they do not fall easily.
3. Be careful where you hang wall clocks, photo-frames, water heaters etc., so that they donot fall in the event of an earthquake.
4. Since some buildings may catch fire due to an earthquake , hence fire fighting equipments should be installed in these buildings.

Some Natural Phenomena PSEB 8th Class Science Notes

• Sparks, in the sky, were believed to be the wrath of God.
• In 1752, Benjamin Franklin established that lightning and spark of amber, were the same thing.
• Electricity is reponsible for sparks or lightning in the sky.
• Rubbing produces electric charges in some materials.
• Similar materials acquire same charges on them, when rubbed with same materials.
• Like charges repel each other.
• Different materials acquire different charges, when rubbed with same materials or different materials.
• Unlike charges attract each other.
• Two kinds of charges are positive and negative.
• The electric charge generated by rubbing is called static electricity.
• Static charges are stationary i.e. they donot move.
• Moving charge constitutes an electric current.
• Earthing is process of transfer of charges from a charged object to the earth. Lightning is nothing but an electric discharge.
• Electric discharge occurs when (i) two clouds come together (ii) clouds come near earth surface (iii) clouds and human body come closer.
• Clouds carry – ve charges on them and on coming in contact with +ve charge produce huge amount of energy in form of bright light and sound.
• A house or a building and even a closed vehicle is the safest place during a thunderstorm.
• Lightning conductor is a device to secure tall buildings from the effect of lightning.
• Electric cell emits electric discharge, which can be up to 650 volts.
• Thunderstorms, cyclones, lightning are natural phenomenon which cause large scale destruction of human life and property.
• Earthquake is also a natural phenomenon.
• Predictions about thunderstorms, cyclones and lightning can be done, but earthquakes can not be predicted.
• An earthquake is sudden shaking or trembling of the earth.
• Floods, Landslides, Tsunami are caused by earthquakes.
• Seismograph is an instrument meant to record seismic waves produced on surface of earth by tremors.
• The intensity of an earthquake is measured in terms of magnitudes on a scale called Richter Scale.
• Symmetrical and mud/timber buildings are to be constructed in seismic prone areas.
• Static Electricity: The electrical charge excited by rubbing is said to be static electricity.
• Earthing: The process of transfer of charges from a charged body to the earth is called earthing.
• Electric Discharge: The process of producing light and sound by clouds is called electric discharge.
• Thunderstorm: A loud noise produced across sky during a rainy day is called thunder storm.
• Lightning: A bright light produced across sky, due to rubbing of two clouds or clouds and earth, is lightning.
• Earthquake: The disturbance deep inside the earth’s crust which cause trembling and shaking of the earth, is called an earthquake.
• Lightning Rod: It is device to secure tall buildings from effect of lightning.

Punjab State Board PSEB 8th Class Science Book Solutions Chapter 15 Some Natural Phenomena Textbook Exercise Questions and Answers.

## PSEB Solutions for Class 8 Science Chapter 14 Chemical Effects of Electric Current

PSEB 8th Class Science Guide Chemical Effects of Electric Current Textbook Questions and Answers

Exercises

Question 1.
Fill in the blanks.
(a) Most liquids that conduct electricity are solutions of ……………….. , ………………. and ………………. .
(b) The passage of an electric current through a solution causes ……………….. effects.
(c) If you pass current through copper sulphate solution copper gets deposited on the plate connected to the ………………… terminal of the battery.
(d) The process of depositing a layer of any desired metal on another material, by means of electricity is called ……………………… .
(a) acid, bases, salts.
(b) chemical
(c) negative (- ve)
(d) electroplating.

Question 2.
When the free ends of a tester are dipped in a solution, the magnetic compass needle shows deflection. Can you explain the reason ?
Deflection of compass needle is due to conduction of electricity through the solution because the solution is good conductor.

Question 3.
Name three liquids, which when tested in a manner shown in fig. may causes the magnetic needle to deflect.

1. Acid
2. Base
3. Acidulated water.

Question 4.
The bulb does not glow in the setup shown in fig. List the possible reasons. Explain you answer.

The set up shows no glowing of the bulb but it does not mean that liquid is not conducting electricity. Liquid may be so weak electrolyte that it can not make the bulb glow. So, to test it for surity, LED can be used, which glows for very minute currents.

Question 5.
A tester is used to check the conduction of electricity through two liquids labelled A and B. It is found that the bulb of the tester glows very brightly for liquid A while it glows dimly for liquid B. You would conclude that.
(i) liquid A is better conductor than liquid B.
(ii) liquid B is better conductor than liquid A.
(iii) both liquids are equally conducting.
(iv) conducting properties of liquids cannot be compared in this manner.
(i) Liquid A is better conductor than liquid B.

Question 6.
Does pure water conduct electricity ? If not, what can we do to make it conducting ?
Pure water does not conduct electricity but it can be made good conductor by adding few drops of dil. sulphuric acid. The water so obtained is called acidulated water.

Question 7.
In case of a fire, before the firemen use the water hoses, they shut off the main electrical supply for the area. Explain why they do this.
Pure water is an insulator but tap water is a good conductor of electricity. To avoid electrocuting, firemen manually shut off the supply before using water hoses.

Question 8.
A child staying in the coastal regions tests the drinking water and also the sea water with his tester. He finds that the compass needle deflects more in case of sea water. Can you explain the reason ?
Since sea water is rich in salt concentration. So, compass needle is more deflected in sea water as compared to the drinking water available in coastal areas.

Question 9.
Is it safe for electrician to carry out electrical repairs outdoor during heavy downpour ? Explain.
No, it is not safe for a wireman to carry out electrical repairs during heavy down pour because water (Impure) is a conductor of electricity. So, wireman can get electric shock.

Question 10.
Paheli had heard that rain water is as good as distilled water. So she collected some rainwater in a clean glass tumbler and tested it using a tester. To her surprise she found that compass needle showed deflection. What could be the reasons ?
No doubt, rain water is pure like distilled water. But then environment is contaminated with many impurities. These impurities get dissolved in rain water, making it a conductor of electric current.

Question 11.
Prepare a list of objects around you that are electroplated.
Electroplated objects.

1. Handle bar of cycle.
2. Wheel rims.
3. Artificial ornaments.
4. Bath taps.
5. Kitchen gas burners.

Question 12.
The process that you saw in Activity 14.7 is used for purification of copper. A thin plate of pure copper and a thick rod of impure copper are used as electrodes. Copper from impure rod is sought to be transferred to the thin copper plate. Which electrode should be attached to positive terminal of the battery and why ?
Thick rod of impure copper is to be attached to positive terminal of battery as pure copper moves to electrode connected to negative terminal of the battery.

PSEB Solutions for Class 8 Science Chemical Effects of Electric Current Important Questions and Answers

Multiple Choice Questions

Question 1.
In order to keep the flow of electricity continue in circuit, which of the following items should be used in place of iron nail in the given circuit.

(a) Graphite
(b) Plastic
(c) Wood
(d) Rubber.
(a) Graphite.

Question 2.
Pankaj knows that pure water is bad conductor of electricity. If you dissolve salt in water then what will happen ?
(а) Water will become good conductor of electricity.
(b) Water will remain bad conductor of electricity.
(c) Water will neither be a good conductor nor a bad conductor of electricity.
(d) None of the above.
(a) Water will become good conductor of electricity.

Question 3.
Which out of the following is insulator of electricity ?
(a) Acid
(b) Bases
(c) Pure water
(d) Solutions of salt
(c) Pure water

Question 4.
Which out of the following is not an insulator ?
(a) Rubber
(b) Plastic
(c) Wood
(d) Copper
(d) Copper

Question 5.
What is the effect of passing electric current through the solution of electrolytes ?
(a) Magnetic effect
(b) Heat effect
(c) Chemical effect
(d) None of these.
(c) Chemical effect.

Question 6.
Which effect of electric current is used in electroplating ?
(a) Magnetic effect
(b) Chemical effect
(c) Heat effect
(d) None of these.
(b) Chemical effect

Question 7.
The availability of some amount of impurities make water:
(a) conductor
(b) insulator
(c) pure
(d) none of these.
(a) conductor.

Question 8.
A tester is used to check the conduction of electricity through two liquids labelled A and B. It is found that the bulb of the tester glows very brightly for liquid A while it glows dimly for liquid B, you would conclude that:
(а) Liquid A is better conductor than liquid B
(b) Liquid B is better conductor than liquid A
(c) Both liquids are equally conducting
(d) Conducting properties of liquids cannot be compared in this manner.
(a) liquid A is better conductor-than liquid B.

Question 1.
Is human body a conductor or an insulator ?
Conductor.

Question 2.
What are conductors ?
Conductors.
Materials like silver, copper, aluminium, iron and human body etc. which allow electric current to pass through them, are called conductors.

Question 3.
What are insulators ? Give two examples.
Insulators.
Materials like wood, rubber, silk, plastic etc. which do not allow electric current to pass through them, are called insulators.

Question 4.
Do all liquids allow electric current to pass through them ?
No.

Question 5.
What is LED ? ,
LED-Light Emitting Diode.

Question 6.
Name the phenomenon of breaking up of a chemical compound under the action of electric current.
Electrolysis.

Question 7.
What do we get on electrolysis of acidulated water ?
Hydrogen gas and Oxygen gas.

Question 8.
Which effect of current is used in electroplating ?
Chemical effect.

Question 9.
Which effect of current makes a bulb glow ?
Heating effect.

Question 10.
How can small current be tested ?
By using LEDs.

Question 11.
Name different effects of electric current.

1. Heating effect,
2. lighting effect,
3. chemical effect and
4. magnetic effect.

Question 12.
Is air an insulator ?
Yes.

Question 13.
Name few liquids which can conduct electricity.
Lime water, lemon juice, vinegar, tap water.

Question 14.
Can conductors be classified as insulators or vice versa under special conditions ?
Yes.

Question 15.
Which commonly used liquids can conduct electricity ?
Solution of acids, bases and salts.

Question 16.
What are electrodes ?
Electrodes.
Metallic rods or plates immersed in electrolytes to make contact with battery, are called electrodes.

Question 17.
By which phenomenon cheap articles are coated with gold or expensive metals ?
Electroplating.

Question 18.
Is electroplating useful process ?
Yes.

Question 1.
Air is a bad conductor of electricity. Show with an experiment.
Take a battery bulb and connect it to a cell and a switch. When the switch is fixed with a safety pin then the current flows and bulb glows, but when safety pin is removed then there is only air between the gap of switch and current does not flow. It shows that air is bad conductor of electricity.

Question 2.
What is electrolysis ?
Electrolysis.
Breaking up of chemical compounds under the action of electric current, is called electrolysis. When we pass electric current through water (acidulated), it breaks up into its constituents : hydrogen and oxygen. Hydrogen is liberated at the cathode whereas oxygen is liberated at the anode.

Question 3.
What is electroplating ?
Electroplating.
Process of electrolysis is used to deposit thin layers of valuable metals (like zinc, silver or gold) on cheaper metals by the passage of electricity through electrolyte to save them from rusting whereas to give them a decorative look. This process is called electroplating.

Question 4.
Give a brief account of LED.

LED.
It is light emitting diode. It glows even when the current is .very small. It consists a bulb with two legs called leads. One leg is longer and other leg is shorter.
Longer leg is attached to +ve terminal of battery and shorter leg is attached to -ve terminal.

Question 1.
Is water a good conductor ? What happens when common salt is added to water ?

Pure or distilled water is an insulator.
Experiment.
Dip two carbon rods in distilled water and connect it to a bulb, 6 V battery and a key. The bulb will not light up showing that distilled water is a bad conductor of electricity.

Now replace distilled water by water mixed with common salt. The bulb will at once light up, when key is introduced. This shows that distilled water is perfectly insulator, impure water specially one containing common salt is highly conducting.

Question 2.
What is electroplating ? Give its uses.

Electroplating.
It is the process by which a costlier metal is deposited on base or cheap metal by passing current through its salt solution. When an electric current is passed through an electrolyte (the compound) breaks up into its constituent ions.

Positive ions are attracted towards cathode (negative electrode) and negative ions are attracted towards anode (positive electrode). This process of electrolysis is used in plating materials with a thin coat of metals is called electroplating.

Uses of Electroplating:

1. Iron is electroplated with nickel or chromium to prevent it from rusting.
2. Artificial jewellery, made from cheap metals is electroplated with expensive metals like gold and silver to give it an attractive look.
3. Handle bars of cycle, wheel rims, car parts etc. are coated with chromium to give a shiny look.
4. Tin cans are made by electroplating a layer of tin on the iron.

Question 3.
How can a spoon be copper plated ?

Experiment.
Take a spoon which is to be electroplated with copper. Take a copper plate and make it anode by connecting it to positive terminal of the battery. Spoon is connected to the negative terminal of battery. A rheostat (Variable resistance); key and ammeter is also connected in series as shown. CuSO4 solution is put in glass vessel. Rheostat is adjusted till a proper current flows through electrolyte [For best electroplating 1A of current should be passed for every 100 cm2 of the surface to be electroplated say if the area of spoon on both sides is 60 cm2, a current of 0.6 A should be passed.] Pass the current for 5-10 minutes, till a layer of shinning copper is seen deposited on spoon.

Chemical Effects of Electric Current PSEB 8th Class Science Notes

• Some materials allow current to pass through them are called conductors and some do not allow the current to pass through them are called insulators.
• Some liquids allow electric current to pass through them, are called electrolytes.
• An electric bulb glows, when electric current passes through it.
• LEDs are used, when the electric current is very small.
• Pure air is an insulator.
• Tap water, salt water, sea or pond water all conduct electricity as they contain impurities and salts in them.
• Pure distilled water is a non-electrolyte.
• Solutions of acids, bases and salts are good electrolytes.
The passage of an electric current through a conducting solution causes chemical reactions.
• Evolution of gas, change of colour of solution and deposits of metal on electrodes are few examples of chemical effects of electric current.
• Fruits and vegetables can also conduct electricity.
• Passing electric current through acidulated water produces bubbles of oxygen and hydrogen on +ve and -ve terminals respectively.
• Electroplating is an important application of chemical effect of electric current.
• Electroplating is process of depositing a layer of any desired (superior) metal on another metallic object (of base metal) by means of electricity.
• Electroplating is very useful to obtain shiny and rust proof articles by covering cheap metals with desired coatings of costlier metals.
• Conductors: Materials which allow current to pass through them, are called conductors.
Insulators: Materials which do not allow current to pass through them, are called insulators.
Electrolysis: It is the process by which a substance (electrolyte) is decomposed into its basic components by passing electric current through it.
• Anode: The electrode, which is connected to the positive end of the battery is called the anode.
• Cathode: The electrode, which is connected to the negative end of the battery is called cathode.
• Electrolyte: A salt solution which conducts electricity through it.

Punjab State Board PSEB 8th Class Science Book Solutions Chapter 14 Chemical Effects of Electric Current Textbook Exercise Questions and Answers.

## PSEB Solutions for Class 8 Science Chapter 13 Sound

PSEB 8th Class Science Guide Sound Textbook Questions and Answers

Exercises

Question 1.
Sound can travel through
(a) gases only
(b) solids only
(c) liquids only
(d) solids, liquids and gases.
(d) solids, liquids and gases.

Question 2.
Voice of which of the following is likely to have minimum frequency ?
(a) Baby girl
(b) Baby boy
(c) A man
(d) A woman.
(c) A man.

Question 3.
In the following statements, tick T against those which are true, and F against those which are false:
(a) Sound cannot travel in vacuum.
True

(b) The number of oscillations per second of a vibrating object is called its time period.
False

(c) If the amplitude of vibration is large, sound is feeble.
False

(d) For human ears, the audible range is 20 Hz to 20,000 Hz
True

(e) The lower the frequency of vibration, the higher is the pitch.
False

(f) Unwanted or unpleasant sound is termed as music.
False

(g) Noise pollution may cause partial hearing impairment.
True

Question 4.
Fill in the blanks with suitable words.
(a) Time taken by an object to complete one oscillation is called ………………….
(b) Loudness is determined by the ………………. of vibration.
(c) The unit of frequency is ……………… .
(d) Unwanted sound is called ………………… .
(e) Shrillness of a sound is determined by the …………………. of the vibration.
(a) Time period,
(b) amplitude,
(c) Hertz (Hz),
(d) noise,
(e) frequency.

Question 5.
A pendulum oscillates 40 times in 4 seconds. Find its time period and frequency.
Number of oscillations
Solution:
Frequency =
= $$\frac{40}{4}$$
= 10 Hz.
Time period = $$\frac{1}{\text { Frequency }}$$
= $$\frac{1}{10}$$
= 0.1 s.

Question 6.
The sound from a mosquito is produced when it vibrates its wings at an average rate of 500 vibrations per second. What is the time period of the vibration ?
Solution:
Frequency 500 vibrations = 500 Hz
Time period = ?
We know, time period = $$\frac{1}{\text { Frequency }}$$
= $$\frac{1}{500}$$
= $$\frac{2 \times 1}{2 \times 500}$$
= $$\frac{2}{1000}$$
= 2 × 10-3 s

Question 7.
Identify the part which vibrates to produce sound in the following instruments ?
(a) Dholak
(b) Sitar
(c) Flute.

 Instrument Vibrating part (а) Dholak Stretched membrane (b) Sitar String (c) Flute Air column.

Question 8.
What is difference between noise and music ? Can music become noise sometime ?
Differences between noise and music:

 Noise Music 1. It is an unpleasant sound. 1. It is a pleasant sound. 2. It causes discomfort. 2. It has a soothing effect. 3. It can lead to health problems. 3. No health problems are associated with it.

Yes, music can become noise when music is too loud, then it becomes a noise.

Question 9.
List sources of noise pollution in your surroundings.
Sources of noise pollution:

1. Sounds of vehicles.
2. Loudspeakers.
3. Working Machines.
4. Bursting of crackers.
5. Desert coolers.
6. Radios and televisions at high volumes.
7. Kitchen appliances.
8. Hawkers.

Question 10.
Explain in what ways noise pollution is harmful to humans.
Harmful effects of noise pollution:

1. Lack of sleep.
2. Hypertension.
3. Anxiety.
4. Partial deafness.

Question 11.

1. Lot of noise due to passing vehicles.
2. Smoke and dust produced by running vehicles.
3. Sound of loud horns of vehicles at the time of traffic jams.

Question 12.
Sketch larynx and explain its function in your own words.

Function of Larynx.
When air passes through the vocal cords, they produce sound. Vocal cords may become loose/thick or tight/thin on vibration, thus causing different types of voices.

Question 13.
Lightning and thunder take place in the sky at the same time and at the same distance from us. Lightning is seen earlier and thunder is heard later. Can you explain why ?
The speed of light is 3 × 108 m/s while that of sound is only 340 m/s. So, lightning and thunder although taking place simultaneously in the sky at the same distance will be seen and heard at different intervals of time.

PSEB Solutions for Class 8 Science Sound Important Questions and Answers

Multiple Choice Questions

Question 1.
The unit of frequency is:
(a) dB
(6) Hz
(c) dB and Hz
(d) None of these.
(b) Hz.

Question 2.
The intensity of disagreeable sound for human ear is
(a) 60 dB
(b) 10 dB
(c) 90 dB
(d) 30 dB.
(c) 90 dB.

Question 3.
Ultrasonic sound is:
(a) Sound of frequency less than 20 Hz
(b) Sound of frequency more than 20 KHz
(c) Sound of frequency 20 Hz to 20000 Hz
(d) None of these.
(b) Sound of frequency more than 20 KHz.

Question 4.
Speed of sound at 20°C is approximately:
(a) 430 m/s
(b) 304 m/s
(c) 340 m/s
(d) 3400 m/s
(c) 340 m/s

Question 5.
The intensity of sound at ordinary inhale is:
(a) 10 dB
(b) 20 dB
(c) 60 dB
(d) 70 dB.
(a) 10 dB.

Question 1.
What is sound ?
Sound. It is a form of energy which produces in us the sensation of hearing.

Question 2.
How is sound produced ?
Sound is produced by vibrations of a body.

Question 3.
Will sound travel in vacuum ?
No, it will require some medium.

Question 4.
Does sound travel in gases ?
Yes.

Question 5.
Does sound travel in liquids ?
Yes.

Question 6.
Does sound travels in solids ?
Yes.

Question 7.
On what factor does loudness of sound depend ?
Loudness of sound depends upon the amplitude of vibrating body.

Question 8.
If an object makes 10 oscillations in a second, then what is its frequency ?
10 Hertz.

Question 9.
Will the sound travel faster, in wood or water ?
In solids, the sound travels faster than liquids. So sound will travel faster in wood than in water.

Question 10.
Sound is produced when objects …………………. .
Sound is produced when objects vibrate.

Question 11.
The number of oscillations per second is called …………………… .
The number of oscillations per second is called frequency.

Question 12.
We can respond to the frequency of sound more than ……………….. hertz and less than ……………… hertz.
We can respond to the frequency of sound more than 20 hertz and less than 20,000 hertz.

Question 13.
Name the section of throat in which the human voice is produced.
Larynx.

Question 14.
Name the characteristics of sound which help us to distinguish different sounds.
The characteristics of sound which distinguish different sounds. The pitch or loudness of the sound.

Question 15.
What is the audible range of human ear ?
Audible Range. The human ear responds to sounds having frequencies 20 hertz to 20,000 hertz.

Question 16.
Define the term pitch.
Pitch. A sensation depending upon the frequency is known as the pitch.

Question 17.
Which sound has higher frequency ? Sound produced by a buzzing mosquito or sound produced by roaring lion.
The frequency of sound produced by a buzzing mosquito will be more than the frequency of sound produced by a roaring lion.

Question 18.
Write the following frequencies in their increasing order:
(i) Voice of a child
(ii) Voice of man
(iii) Voice of a woman.
Voice in increasing order of their frequencies:
Voice of a man < Voice of a child < Voice of a woman.

Question 19.
How do we hear sound ?
When sound waves travelling through air strike our ears, diaphragm of ear starts vibrating. These vibrations reach the ear nerves by small bones and send the messages to our brain and which we hear.

Question 20.
What is length of vocal cords in man ?

Question 21.
Unpleasant sounds are called ………………. .
Noise.

Question 22.
Which sound is produced by musical instruments ?
Musical sound.

Question 23.
What is unit of loudness of sound ?
Decibel (dB).

Question 24.
Name an instrument with pleasant sound.
Harmonium/Guitar/Piano.

Question 25.
What is hearing impairment ?
The disability to hear sounds is hearing impairment.

Question 26.
What are causes of hearing impairment ?
Ear disease, injury, age and loud noise.

Question 27.
Give an example of loud noise.

1. Sound produced by machinery in a factory.
2. Loudspeakers at full volume.

Question 28.
At which unit, sound becomes harmful ?
More than 80 dB (Average factory range).

Question 29.
Which is the major cause of noise pollution ?
Vehicles.

Question 30.
Which natural organism is important to reduce noise pollution ?
Plants and trees.

Question 31.
What is noise pollution ?
Noise Pollution. Presence of excessive or unpleasant sound in the atmosphere is called, noise pollution.

Question 1.
Define the term time period, frequency and amplitude.
Time Period.
It is the time taken by a vibrating particle to complete one vibration.

Frequency.
The number of oscillations per second is called the frequency of the oscillation. Frequency is measured in hertz [Hz].

Amplitude.
The maximum distance through which a vibrating body is displaced from its central resting position, is called amplitude of oscillations.

Question 2.
One astronaut speaks with another astronaut on Moon. Can the other astronaut listen to the first astronaut ?
There is no atmosphere on the moon, thus, the astronauts cannot listen to each other. Therefore, a material medium is required for the propagation of sound.

Question 3.
Sound produced by a mosquito is quite different from the roar of a lion. Explain.
The loudness of sound depends upon the amplitude of the wave. A mosquito produces sound by the vibration of its wings, in open air while the lion roars by the vibration of its vocal chords. The amplitude of the sound produced by mosquito will be less than the sound produced by a lion. The pitch and quality of the two sounds is quite different, which makes the two sounds different and distinguishable.

Question 4.
Explain with simple experiment to show that sound propagates through solid substance.
Experiment.
Connect two empty match boxes by tying them with the two ends (15 to 20 m long). Request your friend to keep one match box close to his ear. By stretching the string speak into one match box. Sound will be heard very clearly by your friend. This shows that sound can propagate through solids.

Question 5.
How is the human voice produced ?
Production of Human voice.
The human voice is the result of vibrations. It is produced in the larynx, a section of the throat. Muscles in the larynx tighten the vocal cords. Air from the lungs rushes past the tight stretched cords and causes the vocal cords to vibrate. The vibrations produced in the vocal cords produce the sound or the voice.

Question 6.
What are ultrasounds ?
Ultrasound.
Our ear does not respond to sounds of frequencies less than 20 hertz or greater than 20,000 hertz. Sound of frequency greater than 20,000 hertz is called ultrasonic. The instrument used for producing ultrasonic sound is ultrasonic CT.

Question 7.
What are the uses of ultrasonic sound ?
Uses of ultrasonic sound:

1. Dogs can listen ultrasonic sounds. So to call their dogs people use ultrasonic sounds.
2. In medical science, ultrasonics are used for forming the images of internal organs of human body.

Question 8.
A boy claps his hands in front of stair-case and hears a musical sound. Explain.
The distance of each step of stair case increases from the boy. When a boy claps, sound will not strike all the steps simultaneously but it will strike in short and regular intervals. The reflected sound from them will be received by the ear in the form of a number of waves at regular intervals. Thus a periodic disturbance produces a musical sound.

Question 9.
Give an activity to prove that sound travels faster in water than in air.
Sound travels faster in water (liquids) than in air, we can prove this fact by the following activity.
Activity. Take a longer balloon and fill it with water. Hold it close to your ear and scratch it gently with index finger on the farther side of the balloon. A sound will be heard. Repeat this experiment with air-filled balloon. On comparing the two sounds, it is proved that sound travels faster in water than in air.

Question 10.
What is noise ? What is its unit ?
Noise.
The unpleasant sounds which are not soft and sweet are known as noise such as sound of machines, automobiles, crackers, etc.
The unit of voice is Decibel (dB).
Noise level is 0-120 dB.

Question 11.
State one difference between noise and a musical sound.
Noise is a sound, which produces disagreeable (jarring) effect on the ear. On the other hand, musical sound produces pleasing effect on the ear of the listener.

Question 12.
How do children with impaired hearing communicate ?
Children with impaired hearing communicate using sign language and with technically developed devices.

Question 13.
Identify the part which vibrates to produce sound in the following instruments ?

 Sr. No. Musical Instrument Sound producing part 1. Flute 2. Dholak

 Sr. No. Musical Instrument Sound producing part 1. Flute Air column 2. Dholak Stretched membrane

Question 1.
Give an activity to show that sound needs medium to be heard.
Sound needs medium.
Sound produced by a vibrating object reaches our ears due to vibrations of the molecules of the medium (air) in succession. If there is no air between the vibrating object and our ear, we would not hear any sound at all. We can study this by the following activity.

Activity.
Take a wooden stick and hold one end close to your ear. Ask your friend to scratch the other end gently, you will hear the sound.

This activity shows that sound can travel through wood. Sound can travel through liquids as well. You can check this by filling a balloon with water. Hold a water filled balloon close to you ear and scratch the opposite surface of the balloons with your finger.You will again hear sound. Now do the same experiment with an air-filled balloon. This time the sound heard is very feeble in comparison.
Thus, we conclude that sound requires a medium to be heard.

Question 2.
What is noise pollution ? What are its causes and its effects ?
Noise pollution.
The unwanted sound which is not soft and is disagreeable to the ear, is called noise. The presence of loud sound in atmosphere is only noise pollution.

Causes of noise pollution.

1. The loud sounds produced by machines in factories.
2. Loud speakers.
3. Generators.
4. Railway stations.
5. Air ports.
6. Music programmes.
7. Crackers.

Effects of noise pollution:

1. The worst effect of noise pollution is deafness.
2. It raises the heart beat.
3. It also effects the pupil of eyes, thus causing night blindness or colour blindness.

Question 3.
What is music ? Name the various types of vibrating objects used in
different kinds of musical instruments.
Music.
Music is the arrangement of sound of different frequencies called notes or swara in a way that it produces pleasing effect on the ear.
In musical instruments, we use vibrating objects such as strings, membranes, and column of air. There are, thus, three families of musical instruments:

1. Stringed instruments (tantu vadya) e.g. violin, sitar, etc.
2. Wind instruments or reed instruments (sushir vadya) e.g. the flutes or the shahnai.
3. Membranous instruments (avanaddha vadya). Many of these are percussions or rhythm instruments e.g. tabla or mridangam.

Sound PSEB 8th Class Science Notes

• Sound is produced by a vibrating object.
• The maximum distance to which a vibrating body moves on either side from its mean position, is called the amplitude of vibration.
• The time taken to complete one oscillation, is called the time period.
• The number of oscillations per second, is called the frequency of oscillation.
• Frequency is measured in hertz (Hz).
• Larger the amplitude of vibration, louder is the sound produced.
• Higher the frequency of vibration, the higher is the pitch.
• For human ears, the audible range of frequency is 20 Hz to 20000 Hz.
• Sound needs a medium for its propagation. It cannot travel in vacuum.
• Light travels much faster than sound.
• Sound may get reflected by an obstacle. Echo is produced due to reflected sound.
• Some surfaces reflect sound better than the others.
• Pleasant effect of sound on the ear is called music while unpleasant sound is called noise.
• In human beings, voice is produced by the vibration of their vocal cords.
• Amplitude: The maximum distance through which a vibrating body is displaced from its mean position.
• Echo: The reflection of sound from an obstacle such as a building or a mountain.
• Frequency: The number of vibrations made by a vibrating body in 1 second.
• Hertz (Hz): The unit of frequency.
• Larynx: Organ of voice in human-beings.
• Loudness: The property of sound which depends upon the amplitude and intensity of the vibrating body.
• Musical Sound: Sound which produces pleasing effect on the ear.
• Noise: Sound which produces disagreeable effect on the ear.
• Ultrasonic: Vibrations having frequency above 20,000 Hz.
• Vibrating Body: An object, moving to and fro about the mean position.
• Vibrations: To and fro motion of an object.
• Vocal Cords: Two pairs of membranous cords or folds in the larynx.

Punjab State Board PSEB 8th Class Science Book Solutions Chapter 13 Sound Textbook Exercise Questions and Answers.