PSEB Notes

This PSEB 8th Class Social Science Notes Chapter 10 The Establishment of East India Company will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 10 The Establishment of East India Company

→ Discovery of a New Sea Route: A Portuguese sailor Vasco-de-Gama discovered the new sea route to India in 1498 A.D.

→ European Communities in India: The Portuguese, the English, the French, and the Dutch came to India for trade.

→ Factories: Trading centers of European Companies in India were called ‘Factories’.

→ The British East India Company: The British established the East India Company in 1600 A.D. It opened trade centres in India and checked the expansion of other European trading companies.

→ The French East India Company: Although the French East India Company was established in 1664 A.D., much later than the British company, yet it made great progress in India.

→ Carnatic Wars: The Carnatic Wars were fought between the British and the French. The British won these three wars.

→ Dupleix: Dupleix was the most capable governor of the French possessions in India.

→ Robert Clive: Robert Clive was an able English military commander. He was the founder of the British Empire in India.

→ The victory of Bengal: The British won the battle of Plassey in 1757 A.D. and the battle of Buxar in 1764 A.D. and thus became the real masters of Bengal.

→ Diwani Rights: The Battle of Buxar ended with the Treaty of Allahabad in 1765 A.D. As a result of this treaty, the British got the ‘Diwani Rights’ of Bengal, Bihar, and Orissa. Now the British were in a position to collect land revenue from these territories.

→ Means of Expansion of Empire: The British Empire was expanded through a number of means such as subsidiary alliance, Doctrine of Lapse, war, Discontinuing pension, etc.

→ Maratha Power: The British defeated powerful Maratha rulers one by one and forced them to accept a subsidiary alliance.

→ The victory of Mysore: The British fought four wars with Hyder Ali and Tipu Sultan to conquer Mysore. The British emerged victoriously.

→ Subsidiary Alliances: Lord Wellesley introduced this system for the expansion of the British Empire. Indian rulers who entered into Subsidiary Alliances with the British came completely under British control.

→ The doctrine of Lapse: This policy was started by Lord Dalhousie. If the ruler of a dependent state had no male child, he could not adopt a son. It meant, if a native ruler died without leaving a son behind, the dependent state would pass automatically into the hands of the British.

This PSEB 8th Class Social Science Notes Chapter 9 When, Where and How will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 9 When, Where and How

→ Division of History:

• World history has been divided into the ancient period, the medieval period, and the modern period.
• In the same way, Indian history has also been divided into three periods i.e. ancient period, the medieval period, and the modern period.

→ Modern Period: Modern period in Europe started in the 16th century but in India, it started in the 18th century.

→ Modern Period in India:

• New powers emerged in the modern period.
• European powers came to India and British rule was established in India.
• Consciousness came among Indians with the spread of western education and national movement started in India.
• It led to the freedom of India in 1947 A.D.

→ Sources of History of Modern India: Main sources of the History of Modern India are:

• Books
• Government Documents
• Newspapers, Magazines, and Pamphlets
• Historical monuments
• Paintings and Sculptures
• Letters of political leaders, etc.

This PSEB 8th Class Social Science Notes Chapter 8 Disaster Management will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 8 Disaster Management

→ Natural Hazard: Any natural event that does not occur frequently but is fast enough to threaten life is called a ‘natural hazard’.

→ Natural disasters: The location of the natural hazards and the intensity with which it occurs lead to what are known as natural disasters. Tsunami, earthquakes, cyclones, floods, etc.

→ Earthquake: The sudden mild or violent shaking of a part of the earth is called an earthquake.

→ Seismograph: An instrument is used to record and measure the vibrations of the earthquake.

→ Man-Made disasters: Bomb explosions, terrorism pollution, Dam-burst, industrial accidents, and epidemics.

→ Disaster Management in India: Many institutions have started courses in disaster management. These include:

• Central Disaster Management Authority, New Delhi.
• Disaster Management National Centre, New Delhi.
• Earthquake Information Centre, I.I.T. Kanpur.
• Disaster Management Institute, Bhopal.
• Indira Gandhi Open University, New Delhi.
• Central Board of Secondary Education, New Delhi.

This PSEB 8th Class Social Science Notes Chapter 4 Our Agriculture will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 4 Our Agriculture

→ Agriculture: It refers to the cultivation of the soil for growing crops and rearing livestock.

→ Crops: The plant species cultivated by human beings for their use.

→ Livestock: Animals and birds which are reared for human use.

→ Crop Specialization: One particular crop suitable for the region is selected by the farmer to be cultivated by him. This is mainly followed for selling the produce in the market.

→ Organic Farming: In this type of farming, organic manure and natural pesticides are used instead of chemicals.

→ Subsistence Agriculture: Farming in which the product is consumed by the farmer’s household.

→ Commercial Agriculture: Farming in which the produce is grown by the farmer for selling in the market.

→ Intensive Agriculture: The farmer produces more by working hard and using the same field over and over again making use of better agricultural means.

→ Extensive Agriculture: The agriculturist tries to get good output by bringing more and more areas under plough.

→ Mixed Farming: Farming in which animals are also used on the farm while growing crops.

→ Multiple Cropping: When two or more crops are grown at the same time on one and the same field.

→ Sericulture: Commercial rearing of silkworms.

→ Horticulture: Growing vegetables, flowers, and fruits for commercial use.

→ Pisciculture: Breeding of fish in specially constructed tanks and ponds.

→ Viticulture: Cultivation of grapes.

→ More than half of the world’s population is directly or indirectly engaged in agriculture.

→ Favourable topography of soil and climate is vital for agricultural activity.

→ Agriculture depends largely on the relief of land, climate conditions, fertility of the soil, and economic factors.

→ Soils not only support the plant but also act as a medium to supply moisture and nutrients.

→ In intensive agriculture, the aim is to get higher yields per unit area.

→ Extensive agriculture is done with machines in sparsely populated areas.

→ In commercial agriculture, most of the crops are produced for the market.

→ The production of fruit and flowers is called horticulture.

→ In a co-operative farm, all the members work and earn proportionately.

→ Crops and livestock are raised together on the same farm in mixed farming.

→ Shifting cultivation is known by different names in different parts of the world, i.e., Juming, Milpa, Ladang, etc.

This PSEB 8th Class Social Science Notes Chapter 3 Minerals and Energy Resources will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 3 Minerals and Energy Resources

→ Rock is a natural substance made up of one a more minerals.

→ Minerals: An inorganic substance which is found in the earth’s crust and it has a definite chemical composition.

→ Metallic minerals: Those minerals contain metals.

→ Minerals may be metallic or non-metallic.

→ Minerals can be ferrous and non-ferrous.

→ Mining: It is an economic activity of extracting valuable minerals from the earth.

→ Mine: It is an excavation in the ground for digging out minerals.

→ Recycling: It means using discarded materials once again.

→ Fossil fuels: They are fuels formed due to the decay of plants and animals millions of years ago.

→ Petroleum: It is derived from Latin words Petra meaning rock and oleum meaning oil. So, petroleum means rock oil.

→ Fossils: The decomposed creatures, minute plants, and animals buried and sedimented for millions of years.

→ Ore: Metals in their raw state as they are extracted from the earth.

→ Grid: Electricity from large power plants is transmitted through a network of power lines.

→ Minerals are extracted by mining, drilling, or quarrying.

→ Minerals can be conserved by recycling.

→ Mining is of four types:

• Opencast
• Shaft
• Quarrying
• Drilling

→ All rocks are composed of one or more minerals.

→ Copper was probably the first metal to be discovered and mined by man.

→ Mining is the extraction of minerals from the earth.

→ The distribution of mineral resources is uneven in India.

→ The main sources of power are coal, petroleum, and natural gas.

→ The non-conventional sources of power are sun, wind, tide, falling water, and geothermal sources.

→ Coal is the basis for all industrial development in the world.

→ About 65 percent of the mineral oil resources are found around the Persian Gulf.

→ Metallic minerals contain metal in raw form.

→ The Non-Metallic minerals do not contain metals.

→ Switzerland has no known mineral deposits in it.

→ A green diamond is the rarest diamond.

→ The oldest rocks in the world are in Western Australia.

→ Norway was the first country in the world to develop hydroelectricity.

This PSEB 8th Class Social Science Notes Chapter 2 Natural Resources will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 2 Natural Resources

→ Conservation: It means using the available resources carefully.

→ Land: The most important resource.

→ Land may be used for agriculture Construction of Roads, Industries, etc.

→ Soil is the uppermost layer of the earth’s crust.

→ Soil Erosion: The removal of soil, especially topsoil, either naturally or as a result of human activity.

→ Land Use: The use of land for different purposes like agriculture, roads, etc.

→ Terrace Farming: The growing of crops on terraces or steps that have been constructed on hillsides.

→ Topography: A detailed account of the features of a tract of country.

→ Strip Cropping: The growing of narrow strips of Cultivated lands, along the contour lines.

→ Shelterbelts: The planting of rows of trees to check the wind movement, to protect the soil.

→ Deforestation: Cutting down trees.

→ Pollution: Contamination of natural resources.

→ Weathering: The breaking up and decay of exposed rocks by temperature changes, plants, animals, etc.

→ Natural vegetation and wildlife are found in the Biosphere.

→ National Park: A natural area designated to protect the ecological integrity of one or more ecosystems for present and future generations.

→ Biosphere resources: Series of protected areas linked through a global network intended to demonstrate the relationship between conservation and development.

→ The land covers about 29 percent of the total surface area of the earth.

→ Land in India actually under cultivation is about 46 percent of the land.

→ The total land resources in our country are fixed.

→ The importance of soils lies in their fertility and capacity to produce crops.

→ Alluvial soils are mostly found in river valleys and floodplains.

→ About 71 percent of the total surface area of the earth is underwater.

→ Wells, tanks, and canals are different sources of irrigation in our country.

→ Natural vegetation can be broadly classified into forests, grasses, and shrubs.

→ Wildlife refers to plants, animals, birds, and other organisms, which live in their natural habitats.

→ Many countries have taken steps to develop ‘biosphere resources’ to protect wildlife.

→ Ninety percent of the world population occupies only thirty percent of the land area.

→ The remaining seventy percent of the land is either sparsely populated or uninhabited.

→ A dripping tap wastes 1200 liters in a year.

→ Soil formation is a very Slow Process. It takes hundreds of years to make just one centimetre of Soil.

→ The thin layer of grainy substance covering the surface of the earth is called soil.

→ In India, soils are of six types.

→ Water can neither be added nor subtracted from the earth.

→ An average urban Indian uses about 135 litres of water every day.

This PSEB 8th Class Social Science Notes Chapter 1 Resources – Types and Conservation will help you in revision during exams.

PSEB 8th Class Social Science Notes Chapter 1 Resources – Types and Conservation

→ Resources: The base for economic strength and prosperity.

→ Types:

• Natural
• Human-made
• Human

→ Utility: What makes an object or substance a resource.

→ Value: It means worth.

→ Stock of Resources: Amount of resources available for use.

→ Patent: It means the exclusive right over any idea or invention.

→ Resources: They are the means which help in attaining given ends or satisfying human wants.

→ Actual or Potential Resources: On the basis of development natural resources may be actual or potential. We know the usage and quantity of the actual resource like coal deposits. A potential resource is not being used.

→ Natural Resources: The gifts of nature, such as land, rivers, plants, animals, etc. They are used by all living things.

→ Human Resources: The human beings living in a particular area or country. It also refers to the ability of humans to use natural resources usefully:

→ Renewable Resources: Those resources which can be obtained continuously for human needs, such as water, plants, etc. They can regenerate themselves.

→ Non-Renewable Resources: Those resources which have a limited or fixed source of supply. Once used they cannot be regenerated easily again.

→ Technology: It is the knowledge to do or make things. It is a human-made resource.

→ Conservation: It is planned and careful use of natural resources so that these resources can be used for a longer period of time.

→ Abiotic or Biotic Resources: On the basis of origin a resource may be: abiotic or non-living-like soil, rocks or biotic-living-like plants, animals.

→ Renewable and Non-renewable Resources: Natural resources may also be classified as renewable-that exist in unlimited quantity like sunlight or non-renewable that are in limited quantity like petroleum.

→ On the basis of distribution, a resource may be ubiquitous like air-found everywhere or localized-found in certain parts only like minerals.

→ Humans have used their intelligence to create certain resources like; vehicles, buildings, roads, etc.

→ Humans themselves are a resource like farmers, labourers, teachers, doctors, etc. Human resource development is essential for further development.

→ We need to conserve resources for fulfilling present and future needs. This is known as sustainable development.

→ Early man was fully dependent upon the environment.

→ Human needs depend upon the natural environment and level of social, cultural, and technological development.

→ All biotic resources can reproduce and regenerate and thus are renewable.

→ The utility of resources largely depends on their location.

→ Anything that can be used to satisfy a need is called resource.

→ Time and technology are two important factors that can change substances into resources.

This PSEB 8th Class Science Notes Chapter 18 Pollution of Air and Water will help you in revision during exams.

PSEB 8th Class Science Notes Chapter 18 Pollution of Air and Water

→ Undesirable change in the physical, chemical, and biological characteristics of air, water, and land, that may harmfully affect human life and other living organisms is termed pollution.

→ The agents or substances which cause pollution of air, water, and land, are called pollutants.

→ Types of Pollution:

• Air pollution
• Water pollution
• Noise pollution
• Soil pollution

→ Air Pollution is the occurrence of or addition of particulate matter, gases, and other pollutants into the air, which can be harmful to human beings, animals, vegetation, buildings, and other assets.

→ Water Pollution is the addition of organic, inorganic, biological, or radiological substances or factors like heat in water which degrades its quality so that it becomes a health hazard and unfit for use.

→ Water pollution is a serious health hazard in India, especially in villages.

→ Ozone depletion has resulted in UV radiations reaching the earth and causes skin cancer, damage to eyes, and defense mechanisms. Acid rain is the result of air pollution.

→ Global warming is due to the slow rise in the earth’s temperature due to an increase in CO₂ concentration in the atmosphere.

→ Global warming can be stopped by cutting down the use of fossil fuels and by reforestation.

→ Industrial processes lead to pollution, this pollution can be controlled and prevented.

→ The heating up of the earth’s atmosphere due to the trapping of infrared radiations by carbon dioxide in the atmosphere is called the greenhouse effect.

→ The main gases present in the air are nitrogen and oxygen.

→ The various gases present in the air are nitrogen, oxygen, carbon dioxide, argon, helium, krypton and xenon, water vapours.

→ Air contains 78% by volume of N₂ and 21% by volume of O₂.

→ Air Pollution: We can define air pollution as the introduction into the atmosphere of materials more than the required amount that will produce or contribute to an adverse effect on the health and well-being of man. Air pollution is not only a general nuisance, but it is also a hazard to the health of plants, animals, and the man himself.

→ Contamination: It is the presence of harmful substances or micro-organisms that may cause disease or discomfort to human beings.

→ Pollution: It is defined as the addition of extraneous constituents to water, air, or land, which adversely affects the natural quality of the environment. Polluted material need not necessarily be contaminated.

This PSEB 8th Class Science Notes Chapter 17 Stars and the Solar System will help you in revision during exams.

PSEB 8th Class Science Notes Chapter 17 Stars and the Solar System

→ The sky is dotted with countless stars, some bright and some not so bright. Some of them twinkle, too.

→ Moon is the brightest object in the sky.

→ Moon, stars, planets, and other objects in sky are known as celestial objects.

→ On full moon day, the moon is fully round, while on new moon day, no moon is visible in the sky.

→ The moon changes its shape from crescent moon to full disc and then disc to no moon. This cycle goes on. These are phases of the moon.

→ The moon reflects the light of the Sun falling on it, as it has not had its own light.

→ The moon revolves around the earth and the earth along with the moon revolves around the Sun.

→ The moon completes one rotation on its axis, as it completes one revolution around the earth.

→ Moon’s surface is dusty, barren, and is full of craters of different sizes.

→ Moon has neither atmosphere nor water.

→ Neil Armstrong was the first human being to set foot on the moon on July 21, 1969.

→ The distance between Sun and the earth is about 150 million kilometers.

→ The nearest star to the earth (next to the Sun) is Alpha Centauri, nearly 40 billion kilometers away.

→ A light-year is a distance traveled by light in one year.

→ Time taken by light to reach from Sun to earth is 8 minutes.

→ Alpha Centauri is 4.3 light-years apart from the earth.

→ Stars are invisible in day time due to bright Sunlight.

→ Stars appear to move from east to west.

→ The movement of stars is due to the rotation of the earth from west to east about its axis.

→ Pole star appears to be stationary in the sky, as it is situated in direction of the earth’s axis.

→ A constellation is a group of stars having a recognizable shape.

→ Ursa major/Saptarishi/Big dipper/The Great Bear is a common constellation during summertime.

→ All stars in the sky revolve around the pole star.

→ Orion, Cassiopeia, etc. are other important constellations.

→ The sun and the celestial bodies (planets, asteroids, comets, meteors, meteorites, satellites) which revolve around the sun form a solar system.

→ Planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Pluto, and Neptune.

→ Sun is the biggest star which is continuously emitting heat and light.

→ Planets are like stars, but without their own light and they revolve around the sun in fixed orbits and rotate around their own axes, too.

→ Any celestial body revolving around another celestial body is called a satellite. Moon is a natural satellite of the earth.

→ Artificial satellites are man-made satellites, which revolve around the earth.

→ Mercury is the nearest planet to the sun. It has no satellites.

→ Venus is neighbour to the earth and shows phases just like the moon.

→ The earth is the only planet with the existence of life on it.

→ Jupiter is the largest planet having 318 times the mass that of earth.

→ Saturn is yellowish in colour. It is beautiful due to the presence of rings around it.

→ Saturn is less dense than other planets and has a large number of satellites.

→ Uranus and Neptune are outermost planets and can be seen only with large powerful telescopes.

→ Inner Planets include Mercury, Venus, Earth, Mars, which are near to the sun and are also known as terrestrial planets.

→ Outer Planets or Jovian planets are far from the Sun and include Jupiter.

→ Saturn, Uranus, Neptune.

→ The gap between the orbits of Mars and Jupiter is occupied by a large number of small objects called asteroids.

→ Comets revolve around the sun in elliptical orbits and their period of revolution around the sun is very large.

→ Halley’s Comet was seen in 1986. It will again appear after 76 years.

→ Shooting Star or a meteor is a small celestial body revolving around the sun and appears like a streak of light in the earth’s atmosphere.

→ Large meteors which do not evaporate completely in the earth’s atmosphere are meteorites.

→ Aryabhatta (the first), INSAT, IRS, Kalpana-1, EDUSAT are Indian artificial satellites.

→ Weather forecasting, television and radio transmission, communication and remote sensing, etc. are some practical applications of artificial satellites.

→ Artificial satellites that revolve around the earth are much closer than the moon.

→ Celestial Objects: The objects found in the sky such as stars, moons, planets, sun, etc are called celestial objects.

→ Light year: The distance travelled by light in one year is called a light year.

→ Satellites: The celestial bodies which revolve around another celestial body are called satellites.

→ Planets: Celestial body revolving around another celestial body.

→ Asteroids: Small objects lying between the orbits of Mars and Jupiter.

→ Constellation: A group of stars having a recognizable shape.

This PSEB 8th Class Science Notes Chapter 16 Light will help you in revision during exams.

PSEB 8th Class Science Notes Chapter 16 Light

→ 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 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.

→ The angle of incidence (∠i) is always equal to the angle of reflection (∠r).

→ The incident ray, normal at the point of incidence, and reflected ray all lie in the same plane.

→ A 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 the term VIBGYOR.

→ Rainbow is a natural phenomenon of dispersion.

→ The 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 endings found in the blind spots of the eye.

→ Two types of resources for visually challenged persons are Non-optical aids and optical aids.

→ The Braille system is one of the most important and popular resources for visually challenged persons.

→ Reflection of Light: The change in direction of light by a shiny surface is called the reflection of light.

→ Screen: The white sheet or surface on which, the image is obtained.

→ Regular Reflection: Reflection takes place from a polished and regular surface.

→ Scattering of Light: Diffusing of light in all directions.

→ Diffused Reflection: The light rays reflected from the non-polished or irregular surface.

→ Incident Ray: A ray of light from a source of light falling on a given surface.

→ Kaleidoscope: An instrument based on multiple reflections 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.

→ The angle of Incidence: The angle between the incident ray and the normal.

→ The 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.

→ The least Distance of Distinct Vision is the minimum distance at which an 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 the 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 a 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 a 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 the persistence of vision.

→ Dispersion of Light is the splitting of white or some other light into its constituents.

→ Perception of Colour:

• The 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 color of the light.
• If cone cells are absent in the eye, then such a person is colour blind.