Category: CBSE Class 8

On this page, you will find Practical Geometry Class 8 Notes Maths Chapter 4 Pdf free download. CBSE NCERT Class 8 Maths Notes Chapter 4 Practical Geometry will seemingly help them to revise the important concepts in less time.

CBSE Class 8 Maths Chapter 4 Notes Practical Geometry

Practical Geometry Class 8 Notes Conceptual Facts

Construction of four-sided figures when

• Four sides and one diagonal are given.
• Two diagonals and three sides are given.
• Two adjacent sides and three angles are given.
• Three sides and two included angles are given.

Some special cases:

• To construct a square when only one side is given.
• To construct a trapezium.

Quadrilaterals basically has ten parts in all, four sides, four angles and two diagonals.

To construct a quadrilateral, we need the measurement of five specified parts.

Before constructing a figure, we need to draw a rough free hand sketch.

Using the properties of the quadrilateral, we can construct parallelograms, squares, rectangles, rhombuses and trapeziums.

On this page, you will find Understanding Quadrilaterals Class 8 Notes Maths Chapter 3 Pdf free download. CBSE NCERT Class 8 Maths Notes Chapter 3 Understanding Quadrilaterals will seemingly help them to revise the important concepts in less time.

CBSE Class 8 Maths Chapter 3 Notes Understanding Quadrilaterals

Understanding Quadrilaterals Class 8 Notes Conceptual Facts

Polygon: A simple closed curve made up of only line segments is called a polygon.
Examples of Polygons:
(i) Triangle

(ii) Quadrilateral

(iii) Pentagon

(iv) Hexagon

Convex and concave polygons

Regular and irregular polygons

Angle sum property: The sum of three angles of a triangle is 180° In AABC, ∠A + ∠B + ∠C = 180°

Sum of all the exterior angles of a polygon is 360°. In the given polygon ABODE, exterior angles ∠1 + ∠2 + ∠3 + ∠4 + ∠5 = 360°.

Kind of Quadrilaterals

(i) Parallelogram

Properties
(a) Opposite angles are equal
(b) Opposite sides are equal
(c) Diagonals bisect each other

(ii) Rhombus:

(a) All sides are equal
(b) Opposite angles are equal
(c) Diagonals bisect each other at 90°

(iii) Rectangle

(a) It is a parallelogram having each angle of 90°
(b) Opposite sides are equal
(c) Diagonals are equal

(iv) Square:

(a) All sides are equal
(b) Each angle is of 90°
(c) Diagonals are equal and bisect each other at 90°

(v) Kite:

(a) Diagonals are perpendicular to each other.
(b) One of the diagonals bisects the other
(c) m∠A = m∠C but m∠B ≠ m∠D

(vi) Trapezium:

A pair of opposite sides is parallel to each other.

On this page, you will find Linear Equations in One Variable Class 8 Notes Maths Chapter 2 Pdf free download. CBSE NCERT Class 8 Maths Notes Chapter 2 Linear Equations in One Variable will seemingly help them to revise the important concepts in less time.

CBSE Class 8 Maths Chapter 2 Notes Linear Equations in One Variable

Linear Equations in One Variable Class 8 Notes Conceptual Facts

1. Statement of equality containing one or more variable (unknown quantity) is called an equation.
For example: 3x – 5 = 6, x – 3y = 7, \(\frac{x}{2}+\frac{y}{3}=5\) , x² + 5 = y² are all equations.

2. Linear equations of one variable contains only one variable.
For example: \(3 x-1=\frac{1}{2}, 5-x=\frac{3}{2}, \frac{6 x}{5}-3=0\)

3. The value of the variable which makes an equation true is called the solution of the equation.
x² + y² = 7 type equations are not linear equations.
(i) Rules for solving an equation.

• Same number can be added to both sides of equality sign (=).
• Same number can be subtracted from both the sides of equality sign (=).
• Same number can be multiplied to both the sides of equality sign (=).
• Both sides of the equation can be divided by the same number.

For example:
3x – 4 = 7
⇒ 3x- 4 + 4- 7+ 4 (adding 4 to both sides)
⇒ 3x = 11
⇒ 3x÷3 = 11÷3 (dividing the both sides by 3)
\(x=\frac{11}{3}\)
Thus, \(x=\frac{11}{3}\) is the solution or root of the equation.

(ii) Rule of transpositions: Any term can be transposed from one side of the equation to the other side by changing its sign, i.e. (+) to (-), (-) to (+), (x) to (-r) and (v) to (x).

On this page, you will find Rational Numbers Class 8 Notes Maths Chapter 1 Pdf free download. CBSE NCERT Class 8 Maths Notes Chapter 1 Rational Numbers will seemingly help them to revise the important concepts in less time.

CBSE Class 8 Maths Chapter 1 Notes Rational Numbers

Rational Numbers Class 8 Notes Conceptual Facts

1. A number which is in the form of \(\frac{p}{q}\), where p and q are co-primes integers and q ≠ 0 is called rational number.
For example, \(\frac{2}{3}, \frac{1}{2}, \frac{4}{5}, 2,-\frac{6}{7}\)

2. Every fraction is a rational number but every rational number need not to be a fraction.
For example: \(\frac{2}{3}\) is a fraction as well as a rational number, o
Whereas -5 is a rational number but it is not a fraction.

3. Standard form of a rational number may be identified when its denominator is positive.
For example: Standard form of is \(\frac{18}{-24} \text { is } \frac{-3}{4}\)

4. Equivalent fraction of \(\frac{p}{q}\) may be denoted by \(\frac{p \times m}{q \times m} \text { or } \frac{p \div n}{q \div n}\)
For example: Equivalent fractions of  \(\frac{12}{16} \text { are } \frac{12+4}{16 \div 4}=\frac{3}{4}\)
or \(\frac{12 \times 2}{16 \times 2}=\frac{24}{32}\)

5. The rational numbers can be compared as:

• \(\frac{a}{b}>\frac{c}{d}\) if and only if ad > bc
• \(\frac{a}{b}=\frac{c}{d}\) if and only if ad = bc
• \(\frac{a}{b}<\frac{c}{d}\) if and only if ad < bc

Properties of rational numbers:
(а) Closure property additions
If a and b are two rational numbers, then a + b will also a rational number
For example: \(\frac{1}{2}+\frac{1}{3}=\frac{1 \times 3+1 \times 2}{6}=\frac{5}{6}\) a rational number.

(b) Commutative property of addition
Two rational numbers can be added in any manner.

(c) Associative property for addition:
While adding three or more rational numbers, they can be grouped in any order.

(d) Additive identity: The sum of any rational number and 0 is always equal to the rational number itself.
Zero is additive identity
For example: 0 + a = a or a + 0 = a

(e) Additive inverse
Additive inverse of \(\frac{a}{b}=-\frac{a}{b}\)
0 is the additive inverse of itself.

Properties of multiplication of rational numbers.
(a) Closure property: The product of two rational number is always a rational number.
For example: Take two rational numbers \(\frac{1}{2} \text { and } \frac{1}{3}\)
∴ \(\frac{1}{2} \times \frac{1}{3}=\frac{1}{6}\) which is also a rational numbers.

(b) Commutative property: The two rational numbers can be multiplied in any order,
i.e. a x b =b x a

(c) Associative property: Three or more rational numbers can be multiplied by grouping in different order,
i.e. (a x b) x c = a x (b x c)

(d) Multiplicative identity: If \(\frac{a}{b}\) is a rational number, then \(\frac{a}{b} \times 1=1 \times \frac{a}{b}=\frac{a}{b}\)
For example: \(\frac{2}{3} \times 1=1 \times \frac{2}{3}=\frac{2}{3}\)
1 is called the multiplicative identity of a rational number.

(e) Distributive property of multiplication over addition.
If \(\frac{a}{b}, \frac{c}{d} \text { and } \frac{e}{f}\) are three rational number,
For example:

For example: Let us consider three rational numbers \(\frac{2}{3}, \frac{4}{5} \text { and } \frac{5}{6}\)

Existence of multiplicative inverse (i.e. Reciprocal)
For every non-zero rational number \(\frac{a}{b}\), there exists its multiplicative inverse \(\frac{a}{b}\).

• i.e… \(\frac{a}{b} \times \frac{b}{a}=1\)
• Reciprocal of zero (0) is not defined.
• 1 and -1 are the only two rational numbers which are Reciprocal of their own.
• Reciprocal of a reciprocal of a number is the number itself.

Representation of rational numbers on number line.

Here A represents \(\frac{1}{3}\) and B represents \(\frac{-2}{3}\) on the given number line.

Rational numbers between two given rational numbers:

Let us consider the rational numbers \(\frac{3}{10} \text { and } \frac{7}{10}\)

So, the rational numbers between \(\frac{3}{10} \text { and } \frac{7}{10} \text { may be } \frac{4}{10}, \frac{5}{10} \text { and } \frac{6}{10}\)

On this page, you will find NCERT Class 8 History Chapter 7 Notes Pdf free download. CBSE Class 8 Social Science Notes History Chapter 7 SST Weavers, Iron Smelters and Factory Owners will seemingly, help them to revise the important concepts in less time.

Weavers, Iron Smelters and Factory Owners Class 8 Notes Social Science History Chapter 7

CBSE Class 8 History Chapter 7 Notes Understanding the Lesson

1. Craft and Industries of India under the British rule:

2. Focused on two industries:

• Textiles
• Iron and Steel} ➝ Both crucial for the Industrial revolution in the modem world.

3. Britain was the foremost industrial nation in 19^th century all because of mechanised production of cotton textiles.

4. Britain also came to be known as the “workshop of the world” after its iron and steel industry started growth from the year 1850.

5. Industrialisation in Britain is closely related to the conquest and colonisation of India. Reason was:

• As in late 18^th century the Company was buying raw material from India at cheaper rates and selling them at huge profit in Europe.
• India was seen as the vast market with the growing industrialisation.

6. The market created in India by buying raw material from India and selling finished goods made in industries of England in India created a huge effect or we can say adverse affect on Indian made crafts and industries.

7. Around 1750’s, during the time when Bengal was captured, India was the world’s largest producer of cotton textiles as it was known for its fine quality and exquisite craftsmanship.

8. Europeans got encountered firstly by the fine cotton cloth of India when it was carried by Arab merchants in Mosul (present-day Iraq).

9. The finely woven clothes were named as ‘Muslin’ by the British.

10. Calico was the general name for all cotton textiles because after the arrival of Portuguese, the cotton textile which they took back to Europe along with spices was named Calico as it was derived from Calicut.

11. The different variety of clothes at that time were:

• Chintz – The word derived from Hindi word Chhint.
• Cossaes (Khassa)
• Bandanna.
• Chint was a cloth with small and colourful flowery design.

12. There was a craze for printed Indian cotton textiles in England and Europe. This was because of their exquisite floral designs, fine texture and relative cheapness.

13. Bandanna refers to any brightly coloured and printed scarf for neck or head. The term was derived from the Indian word ‘Bandanna’. Produced by method of Tye and Dye.

14. The Calico Act was passed in 1720, banning use of printed cotton textiles – chintz in England. This happened because:

• Wool and silk makers started protesting against the import of Indian cotton textiles.
• The protest was due to their worry of the popularity of Indian textiles.

15. Textiles of England at beginning was unable to complete with the Indian textiles.

16. Indian designs were imitated and printed in England on Muslin, a plain unbleached Indian cloth.

17. Competition with the Indian textiles concluded with the new innovations. In 1764, the spinning jenny was invented by John Kaye resulting in increase of productivity of the traditional spindles.

18. In 1786, invention of steam engine revolutionized cotton textile weaving.

19. Indian textiles dominated the world till the end of 18^thcentury.

20. Weavers were people from communities specialised in weaving, e.g. the tanti weavers of Bengal, the julahas or momin weavers of north India, sale and Kaikollar and devangs of south India.

21. Spinning, the first stage of production, was mostly done by women.

22. Charkha and takli were the household instruments.

23. Rangrez were the dyer of thread for cotton textiles.

24. Chhipigars were the specialised people in block printing.

25. The development of cotton industries in Britain adversely affected textile producers in India in different ways:

• Competition rose
• Exporting textiles to England was getting difficult due to high duties on India textiles.

26. By the beginning of 19^th century, English made cotton textiles successfully ousted Indian goods from traditional market in Africa, America and Europe, adversely hitting the different weavers in India.

27. By 1830’s British cotton cloth flooded Indian markets, by 1880, 2/3^rf of all cotton clothes worn by Indians were made of cloth produced in Britain.

28. Handloom weaving never died completely in India.

29. Sholapur of west India and Madura of south India were the towns which emerged as important new centres of weaving in the late 19^thcentury.

30. After Mahatma Gandhi urged people for boycotting imported textiles and to use hand-woven cloths.

• Khadi became a symbol of nationalism.
• Charkha represented India.
• Charkha was even put at centre of tricolour flag which was adopted by Indian National Congress in 1931.

31. The weavers and spinsters who lost their livelihood started working as agricultural labourers.

• Some went out of country to work in plantations in Africa and South America.
• Some found work in new established cotton mills.

32. The first cotton mill of India was set up as a spinning mill in Bombay in 1854.

33. Bombay grew as an important port for the export of raw cotton.

34. Mills came up in other cities too, first mill in Ahmedabad was started in 1861.

35. For the first few decades, the textile factory industry in India faced many problems. They were unable to compete with the cheap textiles imported from Britain.

36. During the first world war when textiles imports from Britain declined then the Indian factories were called upon to produce clothes for military supplies.

37. Story of Indian steel and iron metallurgy starts with Tipu Sultan – the man who died fighting with his sword in his hand.

• The Sword is now a valuable collection in the museums of England.
• The quality of sword to easily rip through the opponent’s armoury was all because of special type of high carbon steel called wootz which was produced all over south India.

38. Francis Buchanan, a traveller, left an account of the technique by which wootz steel was produced in many hundreds of smelting furnaces in Mysore.

39. Wootz, an anglicised version of the Kannada word Ukku, Tamil word – hukker and Malayalam word – urukku, all meaning steel.

40. The Wootz making process was completely lost by mid 19^th century because the imports of iron and steel from England displaced the iron and steel produced by craftspeople in India.

41. By late 19^th century, the craft of iron smelting was in decline.

• Reason behind this includes forest laws that prevented people from entering the reserved forests. Entering in forests was banned so gathering and finding wood for charcoal was getting impossible with the days.
• High taxes were imposed on entering and using forest produce.

42. By the early 19th-century artisans producer of iron and steel-faced competition after ironsmiths started using iron imported from Britain to manufacture utensils and implements.

43. Jamsetji Tata had decided to spend a large part from his fortune to build a big iron and steel industry in India and for that identifying the source of fine quality iron ore was under process.

44. The Agarias were the people found carrying basket loads of iron ore which were derived from the hill nearby, declared as one of the finest ores in the world and the hill name was Rajhara hills. This hill was discovered when in the hot month of April, Charles Weld an American geologist and Dorabji Tata (eldest son of Jamsetji) were travelling in Chhattisgarh in search of the iron ore deposit.

45. Industrial township – Jamshedpur was set up on the banks of the river subamarekha as the water source was near the iron ore deposits.

46. TISCO – Tata Iron and Steel Company began producing steel in 1912. It was set up at opportune time when India use to import steel manufactured in Britain.

47. Railway expansion in India provided huge market for rails produced by Britain.

48. With the set up of TISCO, situation was changing. Indian railway turned forward TISCO after the first world war outbreak and decline in the imports of British steel was seen.

49. Same was with the case of iron and steel as it was with cotton textiles both saw the industrial expansion at time when the British imports in India got declined.

50. During First World War and after Nationalist Movement developed and the industrial class became stronger, the demand for the government protection became louder struggling to retain its control over India.

Weavers, Iron Smelters and Factory Owners Class 8 CBSE Notes Important Terms

Spinning Jenny: A machine by which a single worker could operate several spindles on to which thread was spun. When the wheel was turned all the spindles rotated.

Aurang: A Persian term for a warehouse – a place where goods are collected before being sold; also refers to a workshop.

Bellows: A device or equipment that can pump air.

Smelting: The process of obtaining metal from rock (or soil) by heating it to very high temperature, or of melting objects made from metal in order to use the metal to make something new.

Stag heaps: The waste left when smelting metal.

Rangrez: The thread of cotton textiles was dyed by the dyer and the dyer was known as Rangrez.

Notes of History Class 8 Chapter 7 Time Period

1720: The British Govt, banned the use of printed cotton textiles in England.

1764: John Kaye invented spinning jenny which increased the productivity of the traditional spindles.

1854: India’s first Cotton mill set up as a spinning mill in Bombay.

1861: The first mill in Ahmedabad was started.

1799: Death of Tipu Sultan.

1912: The Tata Iron and Steel Company (TISCO) that came up began producing steel.

1914: The First World War begun.

On this page, you will find NCERT Class 8 History Chapter 3 Notes Pdf free download. CBSE Class 8 Social Science Notes Geography Chapter 3 SST Mineral and Power Resources will seemingly, help them to revise the important concepts in less time.

Mineral and Power Resources Class 8 Notes Social Science Geography Chapter 3

CBSE Class 8 Geography Chapter 3 Notes Understanding the Lesson

1. Rocks on this earth have several materials mixed in term that are called minerals and minerals are scattered throughout the earth’s rocky crust.

2. Mineral is a naturally occurring substance that has a definite chemical composition.

3. Minerals are formed in different types of geological environments under varying conditions created by natural processes without any human interference.

4. Mineral can be identified on the basis of the physical properties such as colour, density, hardness and chemical property such as solubility.

5. There are over three thousand different minerals and they are classified on the basis of composition and are classified mainly as metallic and non-metallic minerals.

6. Metallic Minerals

• Contain metal in raw form.
• Metals are the hard substances that conduct heat and electricity and have characteristics lustre or shine.
• Metallic minerals may be ferrous or non-ferrous.

7. Ferrous Minerals

• Like iron ore, manganese and chromites contains iron.

8. Non-ferrous Minerals

• Does not contain iron.
• May contain other metals such as gold, silver, copper or lead.

9. Non-metallic Minerals

• Do not contain metals.
• Limestone, mica and gypsum are examples of such minerals.
• The mineral fuels like coal and petroleum are also non-metallic minerals.
• Minerals can be extracted by mining, drilling or quarrying.

10. Mining are of two types:

• Open-cast mining
• Shaft mining

11. Mining is the process of taking out minerals from rocks buried under the earth’s surface.

12. Open-cast mining is when minerals that lie at shallow depths are taken out by removing the surface layer and deep bores called shafts have to be made to reach mineral deposits that lie at great depths and this process is called shaft mining.

13. Drilling is when petroleum and natural gases occur far below the earth’s surface are taken out by deep bored wells.

14. Quarrying is the process in which minerals that lie near the surface are simply dug out.

15. Minerals occur in different types of rocks and these are found in igneous rocks, metamorphic rocks and some occur in sedimentary rocks.

16. Asia

• China and India have large iron ore deposits and the continent produces more than half of the world’s tin.
• Asia also has deposits of manganese, bauxite, nickel, zinc and copper.

17. Europe

• Leading producer of iron ore in the world.
• Minerals deposits of copper, lead, zinc, manganese and nickel are found in eastern Europe and European Russia.

18. North America

• The mineral deposits in North America are located in three zones:
•  the Canadian region north of the Great Lakes.
• the Appalachian region.
• the mountain ranges of the west.

19. Western Cordilleras have vast deposits of copper, lead, zinc, gold and silver.

20. South America

• Brazil is the largest producer of high-grade iron ore in the world.
• Chile and Peru are leading producers of copper.
• Brazil and Bolivia are among the world’s largest producers of tin.
• South America also has large deposits of gold silver, zinc, chromium, manganese, bauxite, mica, platinum, asbestos and diamond.

21. Africa

• Rich in mineral resources.
• World’s largest producer of diamonds, gold and platinum.
• South Africa, Zimbabwe and Zaire produce a large portion of the world’s gold.
• Oil is found in Nigeria, Libya and Angola.

22. Australia

• Largest producer of bauxite in the world.
• Leading producer of gold, diamond, iron ore, tin and nickel.
• Kalgoorlie and Coolgardie areas of western Australia have the largest deposits of gold.

23. Antarctica

• Geology of Antarctica is sufficiently well known to predict the existence of variety of mineral deposits, some probably large.
• Significant size of deposits of coal in the Transantarctic Mountains and iron near the Prince Charles Mountains of East Antarctica is forecasted.

24. Distribution in India

25. Iron

• Deposit of high grade iron ore in India.
• The mineral is mainly found in Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, Goa, Maharashtra and Karnataka.

26. Bauxite

• Major bauxite producing areas are Jharkhand, Odisha, Chhattisgarh, Madhya Pradesh, Gujarat, Maharashtra and Tamil Nadu.

27. Mica

• Mica deposits mainly occur in Jharkhand, Bihar, Andhra Pradesh and Rajasthan. India is the largest producer and exporter of mica in the world.

28. Copper

• Mainly produced in Rajasthan, Jharkhand, Madhya Pradesh, Karnataka and Andhra Pradesh.

29. Manganese

• Deposits lie in Maharashtra, M.P, Chattisgarh, Odisha, Karnataka and Andhra Pradesh.

30. Limestone

• Major producing states in India are Bihar, Jharkhand, Odisha, M.P, Chattisgarh, Rajasthan, Gujarat and Tamil Nadu.

31. Gold

• Kolar in Karnataka has deposits of gold in India.
• These mines are among the deepest in the world making the mining of this ore a very expensive process.

32. Salt

• Obtained from sea, lakes and rocks.
• India is one of world’s leading producers and exporters of salt.

33. Uses of Minerals

• Minerals are used in many industries. Those used in gems are usually hard. Silicon is obtained from quartz and Aluminium is obtained from its ore bauxite.
• Minerals are non-renewable resources that takes thousands of years for the formation and concentration of minerals. The rate of formation is much smaller than that of its consumption.
• To conserve mineral resources it is necessary to reduce wastage in the process of mining and with the recycling of metals is another way in which the mineral resources can be conserved.

34. Power resources

• Science and technology changes the lifestyles very fastly.
• Power or energy plays vital role in our lives.
• Power resources are broadly categorised as conventional and non-conventional resources.

35. Conventional sources

• These are those energies which have been in common use for a long time.
• Firewoods and fossil fuels are the two main conventional energy.

Firewood	Fossil Fuel
Widely used for cooking and heating.	Remains of plants and animals which were buried under the earth for millions of years got converted by the heat and pressure into fossil fuels.

36. Fossil Fuel

• The reserve of these minerals are limited.
• Rate at which they are consumed due to rapid growth in population might be the reason that they get exhausted soon.

37. Coal

• Most abundantly found fossil fuel.
• Electricity from coal is called thermal power.
• Coal is referred to as buried sunshine because coal which is used today was formed millions of years ago when giant ferns and swamps got buried under the layers of earth.

38. Petroleum

• It is found between the layers of rocks and is drilled from oil fields located in off-shore and coastal areas. Then this is sent to refineries which process the crude oil and produce a variety of products.
• Petroleum and its derivatives are called Black Gold because they are very valuable.

39. Natural gas

• Found with petroleum deposits and is released when crude oil is brought to the surface.
• Very few countries of the world have sufficient natural gas reserves of their own.

40. Hydel Power

• Rainwater or river water stored in dams is made to fall from heights. The falling water flows through pipes inside the dam over turbine blades placed at the bottom of the dam and the moving blades then turn the generator to produce electricity. This is called hydroelectricity.
• One-fourth of the world’s electricity is produced by hydel power.

41. Non-Conventional Sources of Energy

• The increasing use of fossil fuels is leading to its shortage. It is estimated that if the present rate of consumption continuous, the reserves of these fuel will get exhausted.
• There is need for using non-conventional sources such as solar energy, wind energy, tidal energy the energy which can be renewed.

42. Solar Energy

• Solar energy trapped from the sun can be used in solar cells to produce electricity.
• The technology of utilizing solar energy benefits a lot of tropical countries that are blessed with abundant sunshine.

43. Wind Energy

Wind an inexhaustible source of energy. Windmills have been used for grinding grain and lifting water since times immemorial. In modem time windmills, the high-speed winds rotate the windmill which is connected to a generator to procedure electricity.

44. Nuclear Power

• Obtained from energy stored in the nucleic of atoms of naturally occurring radioactive elements like uranium and thorium.
• These fuels undergo nuclear fission in nuclear reactors and emit power.
• The greatest producers of nuclear power are U.S.A and Europe.
• In India Thorium is found in large quantities in Monazite sands of Kerala.
• The nuclear power stations in India are located in Kalpakkam in Tamilnadu, Tarapur in Maharashtra Ranapratap Sagar near Kota in Rajasthan, Narora in Uttar Pradesh and Kaiga in Karnataka.

45. Geothermal Energy

• Heat energy obtained from the earth is called geothermal energy.
• The temperature in the interior of the earth rises steadily as we go deeper and some times this heat energy may surface itself in the form of hot springs. This heat energy can be used to generate power.
• USA has the world’s largest geothermal power plants.
• In India, geothermal plants are located in Manikaran in Himachal Pradesh and Puga Valley in Ladakh.

46. Tidal Energy

• Energy generated from tides is called tidal energy.
• Tidal energy can be harnessed by building dams at narrow openings of the sea. During high tide the energy of tides is used to turn the turbine installed in the dam to produce electricity.
• Russia, France and the Gulf of Kachchh in India have huge tidal mill farms.

47. Biogas

• Organic waste such as dead plant and animal material, animal dung and kitchen waste can be converted into a gaseous fuel called biogas.
• The organic waste is decomposed by bacteria in biogas digesters to emit biogas which is essentially a mixture of methane and carbon dioxide.
• Energy exists on our earth in several forms but saving energy rather than wasting it is more compulsory because the energy saved is the energy generated.

Mineral and Power Resources Class 8 CBSE Notes Important Terms

Mineral: a naturally occurring substance that has a definite chemical composition is a mineral.

Rock: An aggregate of one or more minerals but without definite composition of constituent of mineral.

Ore: Rocks from which minerals are mined are known as ores.

Mining: The process of taking out minerals from rocks buried under the earth’s surface is called mining.

Quarrying: Minerals that lie near the surface are simply dug out, by the process known as quarrying.

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

Geothermal Energy: Heat energy obtained from the earth is called geothermal energy.

Tidal Energy: It is the energy generated from the tides.

On this page, you will find NCERT Class 8 Civics Chapter 8 Notes Pdf free download. CBSE Class 8 Social Science Notes Civics Chapter 8 SST Confronting Marginalisation will seemingly, help them to revise the important concepts in less time.

Confronting Marginalisation Class 8 Notes Social Science Civics Chapter 8

CBSE Class 8 Civics Chapter 8 Notes Understanding the Lesson

1. The choice of struggle depended upon on the circumstances that the marginalized found themselves in.

2. The Fundamental Rights in the Constitution are available to all Indians equally. As far as the marginalized are concerned, they deserve these rights in two ways:

3. Marginalized have forced the government to recognise the injustice done to them.

4. Marginalized people have insisted that the government enforces these laws.

5. Article 17 of the Constitution states that untouchability has been abolish. In vital sense to society, untouchability is a punishable crime.

6. Article 15 of the Constitution states that no citizen of India shall be discriminated on the basis of religion, race, sex or place of birth.

7. The above-mentioned articles from the Constitution help to strengthen the argument against untouchability.

8. Dalits have used these to seek equality where it has been denied to them. They have drawn the attention of the government of India to the Constitution, demanding that the government abide by it and do justice to them.

9. Dalits and other minority groups have particularly drawn upon the right to freedom of religion and cultural and educational rights.

10. By granting different forms of cultural rights, the Constitution tries to ensure cultural justice to the people from different culture.

11. There are specific laws and policies for the marginalized, in our country. There are policies and schemes that emerge through other means like setting up of committee or by undertaking a survey etc. The government then makes an effort to promote such policies in order to give opportunities to the specific groups.

12. Both State and central governments create specific schemes for implementation in tribal areas or in areas that have a high Dalit population.

13. In addition to providing certain facilities, the government also operates through laws to ensure that concrete steps are taken to end inequality in the system.

14. The reservation policy works as Governments across India have their own list of Scheduled Castes, Schedule Tribes and backward and most backward castes. The central government too has its list. The students or person seeking benefits from government are expected to furnish proof of their caste or tribe status in the form of caste and tribes certificates.

15. Our country also has specific laws that guard against the discrimination and exploitation of marginalized communities.

16. The Scheduled Castes and the Scheduled Tribes (Prevention of Atrocities) Act, 1989 was framed in 1989 in response to demands made by Dalits and others that the government must take seriously the ill treatment and humiliation Dalits and tribals face in an everyday sense.

17. The Act contains a very long list of crimes, some of which are too horrible even to contemplate.

18. The Act does not only describe horrible crimes, but also lets people know what dreadful deeds human being are capable. Laws such as these seek to both punish as well as influence the way we think and act.

19. The Act distinguishes several levels of crimes.

20. Firstly: It lists made of humiliation that are both physically horrible and morally reprehensible and seeks to punish those who:

• force member of a SC’or a ST to drink or >eat any inedible or obnoxious substance.
• forcibly removes clothes from the person of a member of a SC or a ST or parades him or her naked or with painted face or body or commits any similar act which is derogatory to human dignity.

21. Secondly: The Act lists the actions that dispossess Dalits and Adivasis of their meagre resources or which force them into performing slave labour. The Act sets out to punish anyone who:

• wrongfully occupies or cultivates any land owned by, or allotted to a member of a SC or a ST or gets the land allotted to him transferred.

22. At another level, the Act recognizes that the crimes against Dalit and tribal women are of a specific kind and, therefore, seeks to penalise anyone who:

• assaults or uses force on any woman belonging to a SC or a ST with intent to dishonour her.

23. The 1989 Act is important for another reason-Adivasis activist refer to it to defend their right to occupy land that was traditionally theirs.

24. Constitution guarantees the right of tribal people to repose their land.

25. The government must draw up plans and policies for the tribals to live and work elsewhere in case tribals have been evicted and cannot go back to their lands.

26. Desire for dignity, equality and respect is not new. It has existed in different forms throughout our history. In a democratic society, similar process of struggle, writing, negotiation and organising need to continue.

Confronting Marginalisation Class 8 CBSE Notes Important Terms

Assertive: An assertive group or person is one that can express themselves and their views strongly.

Confront: to come face to face or to challenge someone or something.

Dispossessed: to possess is to own something and to be dispossessed is to have to give up ownership or to give up authority.

Ostracise: This means to exclude or banish an individual or a group.

Policy: A Stated course of action that provides direction for the future, set goals to be achieved or lays out principles or guidelines to be followed and acted upon.

On this page, you will find NCERT Class 8 History Chapter 2 Notes Pdf free download. CBSE Class 8 Social Science Notes Geography Chapter 2 SST Land, Soil, Water, Natural Vegetation and Wildlife Resources will seemingly, help them to revise the important concepts in less time.

Land, Soil, Water, Natural Vegetation and Wildlife Resources Class 8 Notes Social Science Geography Chapter 2

CBSE Class 8 Geography Chapter 2 Notes Understanding the Lesson

1. There is difference in the quality of land, soil, water, natural vegetation, animal and the usage of technology and the availability of such resources is the main reason why the different places on the earth differ from each other.

2. Land:

• The most important natural resource which covers only about 30% of the total area of the earth’s surface and not all parts of its are habitable.
• The uneven distribution of population in different parts of the world is mainly due to varied characteristics of land and climate.

3. Land use:

• Land is used for different purposes such as agriculture, forestry, mining, building houses, roads, setting up industries. This is commonly termed as Land use.
• The use of land is determined by the physical factors such as topography, soil, climate, minerals and availability of water.
• Human factors such as population and technology are also important determinants of land use pattern.
• On the basis of ownership land can be classified into private land and community land.
• Private land: owned by individuals.
• Community land: owned by the community for common uses.
• The community lands are also called common property resources.
• The vast changes in the land use pattern also reflect the cultural changes in the society.
• Because of expansion of the agriculture and constructive activities the major threats like land degradation, landslides, soil erosion, desertification are created.

4. Soil:

• The thin layer of grainy substance covering the surface of the earth is called soil.
• It is made up of organic matter, minerals and weathered rocks found on the earth. This happens through the process of weathering.

5. Factors of soil formation:

• The major factors are the nature of the parent rock and climatic factors.
• Topography, role of organic material and time taken for the composition of soil formation are also some other factors of soil formation. All these differ from place to place.

6. Degradation of soil and conservation measures:

• Soil erosion and depletion are the major threats to soil as a resources.
• Factors that lead to soil degradation are deforestation, overgrazing, overuse of chemical fertilizers or pesticides, rain wash, landslides and floods.
• Methods that are useful for the purpose of soil conservation are:

7. Mulching: The bare ground between plants is covered with a layer of organic matter like straw which helps in retaining the soil moisture.

8. Contour barriers: In this stones, grass, soil are used to build barriers along contours. Trenches are made in front of the barriers for collecting water.

9. Rock dam: Rocks are piled up to slow down the flow of water and this prevents gullies and further soil loss.

10. Terrace farming: In this broad flat steps or terraces are made on the steep slopes so that flat surfaces are available for the growing of crops and this reduces surface run off and soil erosion.

11. Intercropping: Different crops are grown in alternate rows and are sown at different times to protect the soil from rain wash.

12. Contour ploughing: Ploughing parallel to the contours of a hill slope to form a natural barrier for water to flow down the slope.

13. Shelterbelts: In the coastal and dry regions, rows of trees are planted to check the wind movement in order to protect soil cover.

14. Water:

• A vital renewable natural resource.
• Three-fourth’s of the earth surface is covered with water.
• Earth is called the ‘water planet’.
• It is found that the life began almost 3.5 billion years back in primitive oceans.
• Freshwater accounts for only about 2.7 per cent.

15 . Only 1 per cent of freshwater is available and fit for the human use found as ground water, as surface water in rivers and lakes and as water vapour in atmosphere.

16. Water can neither be added nor substrated from the earth. Its total volume remains constant.

17. Water cycle: Cycling through the oceans, the air, the land and back again, through the process of evaporation, precipitation and run-off. This process is referred to as the water cycle.

18. Water shortage may be a consequence of variation in seasonal or annual precipitation or the scarcity caused by overexploitation and the contamination of the water resources.

19. Even though water is been categorised under the renewable resource category, its overuse and pollution make it unfit for use.

20. There is scarcity of water in many regions of the world and shortage of water may be a consequence of variation in seasonable on annual precipitation.

21. The scarcity is caused by over-exploitation and contamination of water resources.

22. In today’s world access to clean and adequate water is the major problem.

23. Discharge of untreated or partially treated sewage, agricultural chemicals and industrial effluents in water bodies are major contaminants which pollutes water with nitrates, metals and pesticides. Most of these chemicals are non-biodegradable and reach human bodies through water.

24. Forest and other vegetation cover slow the surface runoff and replenish underground water. Water harvesting saves water runoff, from the surface.

25. The valuable resources of water can be conserved by using and adopting the different means of irrigation.

26. In the eastern and northeastern humid regions of India bamboo, grows in plenty.

27. Silk is obtained from silk worms that are bred on Mulberry trees.

28. Biosphere is the narrow zone of contact between the lithosphere, hydrosphere and atmosphere where the natural vegetation and wildlife do exist.

29. The life supporting system in the biosphere where the living beings are inter-related and interdependant on each other for survival is known as the ecosystem.

30. Wildlife includes animals, birds, insects as well as aquatic life forms which all are integral for maintaining balance in the ecosystem.

31. The growth of vegetation depends primarily on temperature and moisture. The major vegetation types of the world are grouped as forests, grasslands, scrubs and tundra.

32. The forests are associated with the areas having abundant water supply.

33. Forests are broadly classified as evergreen and deciduous depending on their sheding of leaves because:

• Evergreen forests do not shed their leaves simultaneously in any season of the year.
• Deciduous forests shed their leaves in a particular season to conserve loss of moisture through transpiration.

34. With the increase in the population of the world there is decrease or we can say rapid decrease in the forest cover all over the world which ultimately creates an urgent need to conserve this valuable resource.

35. Forests are known as our wealth in which plants give shelter to the animals and together they maintain the ecosystem.

36. Changes of climate and human interferences can cause the loss of natural habitats for the plants and animals. Many of the species have became vulnerable or endangered and some are on the verge of extinction.

37. Poaching is one of the main reasons behind the shark decline in the number of particular species. Increasing awareness can help in the conservation.

38. National parks, wildlife sanctuaries, biosphere reserves are made to protect our natural vegetation and wildlife.

39. There will be the balance in the environment if the relative number of species is not disturbed.

40. Awareness programmes likes social forestry and Vanamohatasava should be organised in order to appreciate the habitat of varied species and protect extinction or indiscriminate killing of species in the ecosystem.

41. Laws are passed against the trade and killing of birds as well as animals in many countries of the world. In India killing lions, tigers, deers, great Indian bustards and peacocks is illegal.

42. CITES an international convention has been established in order to list several species of animals and birds in which trade is prohibited.

43. It is an ethical duty of every citizen to conserve plants and animals.

Land, Soil, Water, Natural Vegetation and Wildlife Resources Class 8 CBSE Notes Important Terms

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

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

Weathering: It is the breaking up and decay of exposed rocks, by temperature changes, frost action, plants, animals and human activity.

Land use: Land is used for different purposes such as agriculture, forestry, mining, building houses, roads and setting up of industries. This is commonly termed as Land use.

Landslide: Defined as the mass movement of rock, debris or earth down a slope.

On this page, you will find NCERT Class 8 Civics Chapter 7 Notes Pdf free download. CBSE Class 8 Social Science Notes Civics Chapter 7 SST Understanding Marginalisation will seemingly, help them to revise the important concepts in less time.

Understanding Marginalisation Class 8 Notes Social Science Civics Chapter 7

CBSE Class 8 Civics Chapter 7 Notes Understanding the Lesson

1. To be marginalised is to be forced to occupy the sides or fringes and thus not be at the centre of things.

2. In the social environment, people or communities may have the experience of being excluded.

3. Their marginalisation can be because they speak a different language, follow different customs or belong to a different religions group from a majority community.

4. They may feel marginalised because they are poor, considered to be ‘low’ social status and viewed as being less humans than others.

5. The sense of difference and exclusion leads to communities not having access to resources and opportunities and in their inability to assert their rights.

6. Marginalisation is seldom experienced in one sphere.

7. Economic, social, cultural and political factors work together to make certain groups in society feel marginalised.

8. Adivasis: The term literally means ‘original inhabitants’. They are communities who lived and often continue to live, in close association with forests.

9. Around 8% of India’s populations is Adivasi.

10. Most important mining and industrial centres in India are located in Adivasi areas.

11. There are over 500 different Adivasi groups in India.

12. Adivasi societies are most distinctive because there is often very little hierarchy among them.

13. Adivasis practise a range of tribal religions that are different from Islam, Hinduism, and Christianity.

14. Adivasis have always been influenced by different surrounding religions like Shakta, Buddhist, Vaishnav, Bhakti and Christianity.

15. Adivasi religions themselves have simultaneously influenced dominant religions of the empires around them.

16. During the 19^th century, substantial numbers of Adivasis converted to Christianity, which has emerged as a very important religion in modern Adivasi history.

17. Adivasis have their own languages which have often deeply influenced the formation of main stream languages.

18. Adivasis are invariably portrayed in very stereotypical ways.

19. Common people have wrong beliefs that Adivasis are exotic, primitive and backward.

20. Adivasis are often blamed for their own lack of advancement as they are believed to be resistant to change or new ideas.

21. Forests were absolutely crucial to the development of all empires and settled civilisations in India.

22. The continuation of life depended heavily on forests, that help recharge many of India’s rivers and, as is becoming cleaner now, crucial to the availability and quality of our air and water. Forests covered the major part our country till the 19th century and the Adivasis had a deep knowledge of, access to, as well as control over most of these vast tracts at least till the middle of the 19^th century.

23. This meant that they were not ruled by large States and empires.

24. Often empires heavily depended on Adivasis for the crucial access to forest resources.

25. In the Pre-colonial world, Adivasis were traditionally ranged hunter-gatherers and nomads and lived by  shifting agriculture and also cultivating in one place.

26. Forest lands have been cleared for timber and to get land for agriculture and industry.

27. Adivasis have also lived in areas that are rich in minerals and natural resources. These are taken over for mining and other large industrial projects.

28. Huge tracts of their lands have also gone under the waters of hundreds of dams that have been built in independent India.

29. India has 54 national parks and 372 wildlife sanctuaries covering 1,09,652 sq. km.

30. Losing lands and access to the forest means that tribals lose their main sources of livelihood and food.

31. Adivasis have migrated to cities in search of work where they are employed for very low wages in local industries or at building or construction sites.

32. 45% of tribal groups in rural areas and 35% in urban areas live below the poverty line.

33. Many tribal children are malnourished. Literacy rates among tribals are also very low.

34. The Adivasis when displaced from their lands, they lose much more than source of income and that is they lose their traditions and customs – a way of living and being.

35. There is an existence of an interconnectedness between economic and social dimensions of tribal life. Destruction in one sphere naturally impacts the other.

36. The term minority is most commonly used to refer to communities that are numerically small in relation to the rest of the population.

37. Size can be a disadvantage and lead to the marginalisation of the relatively smaller communities. Thus, safeguards are needed to protect minority communities against the possibility of being culturally dominated by the majority.

38. According to 2001 census, Muslims are 13.4% of India’s population and are considered to be a marginalised community in India because in comparison to other communities, the Muslims have been deprived of the benefits of social and economic development over the years.

39. Recognising that Muslims of India were lagging behind in terms of various development indicators, the government set up a high level committee in 2005. Chaired by Justice Rajinder Sachar, the committee examined the social, economic and educational status of the Muslim community.

40. The social marginalisation of Muslims in some instances has led to them migration from places where they have lived, this process leading to the ghettoisation of the community.

41. Sometimes, prejudice leads to hatred and violence.

42. Marginalisation is a complex phenomenon requiring a variety of strategies, measures and safeguards to redress this situation.

43. There are different reasons for each of the communities that are being marginalised.

44. Marginalisation is linked to experiencing disadvantage, prejudice and powerlessness.

45. Marginalisation results in having a low social status and not having equal access to education and other resources.

46. Marginalised communities always want to maintain their cultural distinctiveness while having access to rights, development and other opportunities.

Understanding Marginalisation Class 8 CBSE Notes Important Terms

Hierarchy: A graded system or arrangement of persons or things. Usually persons at the bottom of the hierarchy are those who have the least power.

Ghettoisation: A ghetto is an area or locality that is populated largely be members of a particular community.

• Ghettoisation refers to the process that leads to such a situation. This may occur due to various social, cultural and economic reasons.
• Often a ‘Ghettoised’ community has few options of moving out, which may lead to them becoming alienated from the rest of the society.

Mainstream: This refers to the main current of a river or stream. Mainstream also refers to people or communities that are considered to be at the centre of a society, i.e. often the powerful or dominant group.

Displaced: This refers to people who are forced or compelled to move from their homes for big development projects including dams, mining, etc.

Militarised: An area where the presence of the armed forces is considerable.

Malnourished: A person who does not get adequate nutrition or food.

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Understanding Our Criminal Justice System Class 8 Notes Social Science Civics Chapter 6

CBSE Class 8 Civics Chapter 6 Notes Understanding the Lesson

1. After a person is arrested by the police, it is a court of law that decides whether the accused person is guilty or not.

2. According to the Constitution, every individual who is charged of a crime has to be given a fair trial.

3. There are 4 key players in the criminal justice system: the police, the public prosecutor, the defence lawyer and the judge.

4. One important function of the police is to investigate any complaint about the commission of a crime.

5. Investigation includes recording statements of witnesses and collecting different kinds of evidence.

6. Based on investigation the police are required to form an opinion. If the police think that the evidence points to the guilt of the accused person, then they file a chargesheet in the court.

7. Police investigations always have to be conducted in accordance with law and with full respect for human rights.

8. The Supreme Court has laid down guidelines that the police must follow at the time of arrest; detention and interrogation.

9. Article 22 of the Constitution and criminal law guarantee to every arrested person the following Fundamental Rights:

10. The Right to be informed about the offence for which the person is being arrested at the time of arrest.

11. The Right to be presented before a magistrate within 24 hrs of arrest.

12. The Right not to be ill treated or tortured during arrest or in custody.

13. Confessions made in police custody cannot be used as evidence against the accused.

14. A boy under 15 yrs of age and women cannot be called to the police station only for questioning.

15. The Supreme court of India has laid down specific requirements and procedures that the police and other agencies have to follow for the arrest, detention and interrogation of any person. These are known as the D.K. Basu guidelines.

16. A criminal offence is regarded as a public wrong that means or that is considered to have been committed not only against the affected victims but against society as whole.

17. In court, it is the Public Prosecutor who represents the interests of the State. The role of the Prosecutors begins once the police has conducted the investigation and filed the chargesheet in the court.

18. A prosecutor must conduct the prosecution on behalf of the State.

19. It is the duty of the prosecutor being an officer of the court to act impartially and present the full and material facts, witnesses and evidence before the court to enable the court to decide the case.

20. The judge conducts the trial impartially and in an open court.

21. The judge hears all the witnesses and any other evidence presented by the prosecution and the defence.

22. On the basis of the evidence presented and in accordance with the law the judge decides whether the accused person is guilty or innocent.

23. For a trial to be fair several different procedures have to be observed.

24. Article 21 of the Constitution that guarantees the Right to Life states that a person’s life or liberty can be taken away only by following a reasonable and just legal procedure.

25. A fair trial ensures that Article 21 of the Constitution is upheld.

26. It is significant that the judge decides the matter only on the basis of the evidence before the court.

27. Every citizen, irrespective of their class, caste, gender, religions and ideological backgrounds gets a fair trial when accused.

28. The rule of law which says that everyone is equal before the law would not make much sense if every citizen were not guaranteed a fair trial by the Constitution.

Notes of Civics Class 8 Chapter 6 Time Period

Accused: This refers to the person who is tried by a court for a crime.

Cognizable: This refers to an offence for which the police may arrest a person without the permission of the court.

Cross-examine: This refers to the questioning of a witness who has already been examined by the opposing side in order to determine the veracity of his/her testimony.

Detention: This refers to the act of being kept in illegal custody by the police.

Impartial: The act of being fair or just and not favouring one side over another.

Offence: Any act that the law defines as a crime.

Witness: This refers to the person who is called upon in court to provide a first-hand account of what he/ she has seen, heard or knows.

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Resources Class 8 Notes Social Science Geography Chapter 1

CBSE Class 8 Geography Chapter 1 Notes Understanding the Lesson

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

2. Utility or usability is what makes an object or substance a resource. For example, water, electricity, rickshaw, vegetable and textbook, etc. have something in common and all have been used by human beings, so they have utility.

3. Things become resources when they have a value. Its use or utility gives it a value and all resources have some value.

4. Value means worth. Some have economic value some do not.

5. Some resources can become economically valuable with time.

6. Time and technology are two important factors that can change substances into resources. Both are related to the needs of the people and people themselves are the most important resource.

7. Resources are classified into following categories:

• Natural resources
• Man-made resources
• Human resources

Natural Resources

8. Resources which are drawn from nature and used without much modification are called natural resources.

9. Natural resources are classified into different groups depending upon their level of development and use; origin; stock and distribution.

10. Based on development and use resources are classified into two groups:

• Actual resources
• Potential resources

11. Actual Resources:

• Resources whose quantity is known and are being used in the present.

12. Potential Resources

• Resources whose entire quantity may not be known and are not being used at present. These could be used in the future.
• The level of technology we have at present may not be advanced enough to easily utilise these resources.

13. Based on their origin, classification of resources can be:

• Abiotic resources – Non-living
• Biotic resources – Living

14. Natural resources are categorised broadly into:

• Renewable resources
• Non-renewable resources

15. Renewable Resources

• Those which get renewed or replenished quickly.
• Some of these are unlimited and even not affected by human activities.

16. Non-renewable Resources

• Those which have a limited stock.
• Once the stocks are exhausted it may take thousands of years to be renewed or replenished.
• On the basis of their distribution resources can be ubiquitous or localized. Those found only in certain places are localized.
• The distribution of natural resources depends upon numbers of physical factors and these factors differ so much over the Earth that distribution of resources is unequal.

17. Human Made resources

Natural substances become resources only when their original form has been changed. People use natural resources to make buildings, bridges, roads, machinery and vehicles, that are known as human-made resources. Even the technology is defined as a human-made resource.

18. Human Resources

People can make the best use of nature to create more resources with the help of their knowledge, skill and technology which they have. This is why human beings are known as special resources. Education and health help in making people a valuable resource.

19. Human Resources Development

• Improvising the quality of skills of people to make them able to create more resources is known as human resource development.

20. Conserving Resources

• Resource conservation is meant by using resources carefully and giving them time to get renewed.
• Sustainable development is defined as balancing the need to use resources and also conserve them for the future needs.
• The future of our planet and its people is co-related with the ability to maintain and preserve the life support system by the nature.

21. It is the duty of people of this Earth to ensure that:

• All uses of renewable resources are sustainable.
• The diversity of life on Earth is conserved.
• The damage to natural environmental system is minimised.

Resources Class 8 CBSE Notes Important Terms

Utility: The state of being useful, profitable or beneficial.

Value: It means worth or considering something to be important or beneficial.

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

Technology: It is the application of latest knowledge and skill in doing or making things.

Origin: The point or place where something begins, arises or is derived.

Stock of resources: It is the amount of resources available for use.

Human resources: Refers to the number and abilities of the people.

Sustainable development: Carefully utilizing resources so that besides meeting the requirements of the present, they also takes care of future generations.