PUSHPALATA VIDYA MANDIR

LINKS FOR ONLINE LEARNING

Following are the links for the second chapter for class 8

MATHS

Exponents and powers

https://youtu.be/g5ZGDNxJwxA

https://youtu.be/wsaH5CARIHI

https://youtu.be/gsYEe-JxS5k

https://youtu.be/P2yeKYke_WE

SCIENCE

Crop production

and management

https://www.youtube.com/playlist?list=PLCzaIJYXP5Ycs7OqYtaSv_nioNI4xNje9

Force and

friction

https://www.youtube.com/playlist?list=PLCzaIJYXP5YcYRg0HWHusmrhQzsCJ4dKb

https://www.youtube.com/playlist?list=PLHOGBLPrsnMqLXSDIVzq3narpRcAduSif

Fibre to fabric https://www.youtube.com/watch?v=PVcUxecTgZ4&feature=youtu.be

WORKSHEETS

CLASS: 8 SUBJECT: Science Chapter 1: Crop Production and Management

1. Humans obtain various food from plants and animals.

Here is a list of some unusual sources of food from plants and animals.

Name the kind of food that we get from these sources.

Food source

The kind of food that we get from the

food source

1. Ducks

2. Cinnamon bark

3. Soya bean

4. Seaweed algae

5. Rose flower

6. Lotus roots

7. Bamboo tree

8. Camel

9. Frog

10. Kangaroo

2. Common sugar and salt are two most important ingredients in our food. Can you differentiate between them?

3. What are the insects, pests and weeds that destroy crops? How do farmers remove these?

4. Before a crop is planted, soil has to be prepared. Here are the steps for soil

preparation: Leveling, Ploughing, Adding Fertilizer or Manure Arrange them in a correct order.

5. Modern agricultural methods give higher crop yields. From the list given below,

identify modern agricultural methods. (Choose 2 options) a. Use of tractors and seed drills

b. Manual sowing

c. Furrow irrigation

d. Genetically modified seeds

e. Hoeing 6. State whether true or false and then give reasons for your answer.

Cultivation of fruits, flowers and vegetables can be done only in the open fields.

Multiple Choice Questions (IBT-based Assessments)

1. Earthworms live inside the soil and ………………………, but during heavy rain they are

seen over land.

a. add humus to it

b. add fertilisers to it

c. sow seeds in it

d. kills weeds in soil

2. ………………… is an agricultural implement that is used for ploughing and is driven by

tractors to save labour and time.

a. Leveller

b. Hoe

c. Cultivator

d. Plough

3. Which of these statements describes a hoe?

i. It is a long rod made of wood or iron plank.

ii. It is used on farms after sowing.

iii. Its bent plate acts as a knife / blade.

a. Option i. is correct.

b. Option ii. is correct.

c. Option iii. is correct.

d. Options i. and iii. are correct.

4. Lara deposited a few gram seeds in a beaker filled with water and kept it for a few

days. Which of these statements best describes her observations?

a. Healthy seeds being lighter float on the surface of water.

b. Damaged seeds being lighter float on the surface of water.

c. Few healthy seeds and damaged seeds float on the surface of water.

d. Damaged seeds being heavier settle down at the bottom.

5. Read the given statements and choose the one that is incorrect.

a. Fertilizers increase the yield of the soil.

b. The excessive use of fertilizers disturb the balance of nutrients in the soil.

c. Fertilizers are generally used in small quantity.

d. Fertilizers are environment friendly.

6. What should a farmer avoid to maintain the fertility of soil?

a. The land must be left uncultivated between two cropping seasons.

b. Different crops must be alternatively grown on the farm.

c. Same type of crops must be grown on the farm every year.

d. Leguminous crops must be grown on the farm every cropping season.

7. Organic manure …………………………………………………

a. enhances water holding capacity of soil.

b. provides balanced nutrient to all plants.

c. provides humus to soil.

d. improves texture of soil.

8. Read the given statements and choose the one that is incorrect.

a. Chemical fertilisers are inorganic salts.

b. Chemical fertilisers are prepared in factory.

c. Chemical fertilisers provide humus to soil.

d. The overuse of chemical fertilisers pollutes the water source.

9. Which of these given pictures depicts a chain pump system used in traditional

irrigation?

a. b.

c. d.

10. Read the given statements and choose the incorrect one.

a. Plants absorb nutrients and water through root.

b. Water is needed for seeds to germinate.

c. Water is needed for flowers and fruits to develop.

d. Water protects plants from pests.

11. A farm used a modern method of irrigation by directly watering the plant root

with drops of water. This is popularly known as ……………………………

a. dhekli system.

b. rahat system.

c. sprinkler system.

d. drip system.

12. Choose the odd one out.

a. Plough

b. Seed drill

c. Chain pump

d. Sickle

13. Imran observed weeds growing along with other plants in his farm. Choose the

wrong statement.

a. Weeds can be removed manually.

b. 4-D is commonly used as a weedicide.

c. Weeds are undesirable plants.

d. Weeds don’t require much water or nutrient.

14. Mini wants to practise crop rotation. Suggest a rabi crop and a kharif crop which

will replenish her field with nitrogen.

a. Mustard, soyabean

b. Maize, paddy

c. Wheat, pea

d. Paddy, maize

15. Sara’s mother placed dried neem leaves in the rice container to protect it from

……………………..

a. rat.

b. moisture.

c. insect.

d. weeds

16. Read the given statements.

i. Seeds require moisture for germination.

ii. Plants absorb nutrient mostly in dissolved form.

iii. Irrigation protects crop from both frost and hot air current.

iv. Irrigation improves soil texture.

Which of these options best describes the need to irrigate crops?

a. i. and ii.

b. i., ii. and iii.

c. i. and iii.

d. i., ii., iii. and iv.

17. Propagation of ginger is usually done using ……………….

a. seed.

b. stem (rhizome).

c. root.

d. leaf.

18. Read the given statements and choose the incorrect one.

a. Ploughing facilitates deep penetration of plant roots into the soil.

b. Ploughing facilitates the growth of weeds in the soil.

c. Ploughing facilitates proper aeration of roots.

d. Ploughing promotes growth of useful soil bacteria.

19. ………………………… is not essential for the growth of maize.

a. High temperature

b. Humidity

c. Low temperature

d. Rainfall

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CLASS: VIII SUB: SCIENCE FORCE AND FRICTION

I Choose the correct option:

1. Two men are pushing a refrigerator from opposite directions. If the man on the

right is applying more force, the refrigerator would move …………………………….

a. to the left.

b. to the right.

c. No where.

2. What happens when a batsman strikes a ball with his bat?

a. The shape of the ball changes.

b. The speed of the ball changes.

c. The state of motion of the ball changes.

3. In the tug-of-war when two teams pull equally hard, the rope …………………

a. moves towards the right.

b. does not move in any direction.

c. moves towards the left.

4. Which of these options results in change in shape and size of the object?

a. Stopping a moving ball.

b. Changing the direction of a car.

c. Squeezing a balloon full of air.

5. Look at the picture and determine the forces working against the kids going

downhill.

a. Muscular force and friction

b. Gravity and friction

c. Magnetic force and friction

6. Which of these surfaces offers maximum friction?

a. Carpet

b. Polished floor

c. Wet soapy floor

7. Kabaddi players apply soil on their hands to ...................................... , thereby

enabling them a better grip of their opponent.

a. increase friction

b. decrease friction

c. make it smooth

8. When we stop pedalling, the cycle eventually comes to a stop due to

……………………… force.

a. muscular

b. gravitational

c. frictional

9. Which of these effects of an applied force does this picture depict?

a. Make a stationary object move.

b. Change the direction of moving object.

c. Change the shape and size of the object.

10. If a stone is tied to a rubber string and hung, then the rubber string stretches

due to ......................... force.

a. muscular

b. gravitational

c. frictional

11. The wheels of a train engine is slipping on an uphill track. What would the

engine crew use on the rails to prevent this?

a. Water; this would reduce the friction.

b. Ice; this would prevent the wheels from sliding downhill.

c. Wax; the rails would be smoother for easier movement.

d. Sand; this would increase the friction.

12. Which of these involves a contact force?

a. Attracting iron fillings by a magnet

b. Exercising with dumbbells

c. Motion of a bomb dropped from a fighter plane

d. Attracting bits of paper by static-charged comb

13. If a stone is tied to a rubber string and hung, then the rubber string stretches

due to ......................... force.

a. muscular

b. gravitational

c. electric

d. frictional

14. Look at the pictures and determine which of these is an example of a non-

contact force.

a. b. c. d

15. Which of these surfaces offers maximum friction?

a. Carpet

b. Polished floor

c. Billiards table

d. Wet soapy floor

16. Force can

a.change the direction of the moving object

b.change the shape of the object

c. change the speed of the object

d. all the above

17. What is the similarity in the shape of an aeroplane and a bird?

a. Both are lightweight.

b. Both have long bodies.

c. Both have streamlined bodies.

18. When a horse jumps up, the force lifting it is from the ……………………..

a. ground.

b. air.

c. rider.

d. horse shoes.

19. A rubber ball travels a short distance on a wooden surface. Look at the pictures

and determine what should be spread / sprinkled to make it go further.

a. b. c. d.

20. __________ is an instance of static friction.

a. Carrom struck by the striker

b. Bicycle moving down the inclined plane

c. Hand is rubbed on a glass

d. To strike a matchstick

II. In the following statements, identify the force.

a. A car driver pushes the brakes to stop the car

b. A tennis player hits a ball back to the opposite court

c. A person lifts a book from a table

d. Moon is revolving around the earth

Force

Push Pull

III. Study the classification or types of forces below.

Can you give at least one example of A, B, C and D?

IV. The same amount of force was exerted on a 500g box while moving it from

start to finish on different surfaces A, B, C and D.

Start Finish

For surface A – For surface C –

the box moved 30 cm the box moved 40 cm

For surface B – For surface D –

the box moved 60 cm the box moved 80 cm

Arrange the four surfaces A, B, C and D in descending order of the frictional

forces between the box and the surfaces, starting with the largest amount of

frictional force. Give reasons for the same.

A B C D

Contact

Force

Non-contact force

Contact

Force

Non-contact

force

Anita

Bunty Sunita

Position X Position Y

V. Four students – Anita, Bunty, Celina and Sunita each at one side of the box,

pushed on the box all at the same time as shown in the diagram below. The box

moved from position X to Y diagonally.

The table below gives the amount of force exerted on the box by each of the four students. Which of the option is correct? Can you justify your answer?

Options Amount of force exerted on the wooden box (N) by each of

the students

Anita Bunty Celina Sunita

A 6.0 7.0 7.0 8.0

B 8.0 9.0 8.0 9.0

C 6.0 4.0 5.0 6.0

D 9.0 9.0 6.0 6.0

VI. Give reasons for the following:

a. It is difficult to walk on sand

b. Lizards and geckos can climb vertically on walls and even on smooth glass surfaces

c. Carom players spread talcum powder on a carom board before playing

d. Swim suit fabrics are designed to have minute ridges and scales like marine animals

e. A cleaning attendant places a warning sign board while cleaning a corridor or a classroom in your school

f. Japan’s magnetic levitating trains (or maglev trains) are the fastest in

the world

g. A shooting star shines brightly while falling through the Earth’s atmosphere

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Celina

CLASS: 8 SUBJECT: Science Chapter 3: Synthetic Fibres and Plastics

1. Column A are the names of natural fibres or materials and their uses; Column

B are the names of artificial fibres or materials which can replace the natural fibres or materials mentioned in Column A.

Match the following

Column A (Natural Fibres / Materials)

Column B (Artificial Fibres / Materials)

Silk for sarees Melamine

Wool for sweaters Neoprene (Artificial rubber)

Coir ropes Acrylic

Bone china dinner plates Nylon

Rubber for tyres Rayon

2. Given below are list of everyday objects that are made from one or more synthetic fibres or materials. Can you name these?

a. Swim wear -------------------------------------------------------------------------.

b. Fishing nets ------------------------------------------------------------------------.

c. Socks -------------------------------------------------------------------------------.

d. Ice cream containers --------------------------------------------------------------.

e. Disposable cups -------------------------------------------------------------------.

f. Mufflers, shawls or stoles ----------------------------------------------------------.

3. A textile mill owner, Upadhya, is in a quandary. He had ordered some

polyester threads and some cotton threads of same colour and same thread thickness. When he received them, he could not make out which spool of threads had polyester threads, and which had cotton threads. He had sent the

2 spools (X and Y) to a test lab to have them identified. Here are the test results.

a. Visual test: Although the 2 spools have identical colours, identical thread

thickness; and each weighing 50 gms, spool X looks bigger than Y.

b. Water resistance test: X does not absorb water, whereas Y does.

c. Strength test: X is stronger than Y.

d. Coil them up: X does not coil up but Y does.

e. Light them with a match stick: X flares up and burns quickly when a

lighted match is brought to it, whereas Y catches fire but the rate of burning

is slow. Can you analyze this data and help Upadhya out?

4. Plastics have entered our daily lives only in the last 50 or more years. How did people live without plastics in early 20th century? Compare and contrast

what materials are used by people now, use items of everyday lives now, with what they had used earlier.

Items of everyday lives Materials used for

these items in early 20th century

Materials used for

these items in early 21st century

a. Water bottles used in fridges

b. Shoes for running

c. Bags for shopping

d. Food containers for storing

e. Mugs and buckets for

bathing

5. Your elder sister Seema was feeling hungry and wanted to cook something in

the kitchen. Your mother asked her to cook whatever she wanted, but since Seema was wearing a synthetic skirt, your mother warned her to change into

a cotton skirt. Did your mother advise Seema correctly? Give reasons for your answer.

6. Comment on this statement: Plastics have not replaced kitchen utensils.

Multiple Choice Questions

1. ……………. is a type of plastic that can be moulded into different shapes

multiple times. a. Bakelite

b. Polyester

c. Melamine

d. Polyethene

2. Allen is a chef. While working in the kitchen, he should wear ……….. clothes.

a. Polyester

b. Rayon

c. Cotton

d. Acrylic

3. What material are these bottles made of?

a. PET

b. Acrylic

c. PVC

d. Terylene

4. The best alternative to wool is ……………………..

a. Rayon.

b. Acrylic textile.

c. Bakelite.

d. Nylon.

5. Which of these options wrongly match the materials to the consumer products?

a. Bakelite – electric switch.

b. Nylon – parachute.

c. PVC – toy.

d. Melamine − PET container. 6. Choose the correct option from (a – d) for the ones given below.

i. Fibres are made from fabrics. ii. Fabrics are made from fibres.

a. i. is correct.

b. ii. is correct. c. i. and ii. are correct.

d. i. is correct only if ii. is correct. 7. The handle of this utensil is made of ………………………. material.

a. Terrycot b. Rayon

c. Polyester d. Bakelite

8. Which of these is not made of plastic?

a. Tyres

b. Threads for surgery

c. Non-stick coating on cookware

d. Uniforms of firemen

9. ……………. is blended with rayon to make carpets.

a. Polywool

b. Polyester

c. Wool

d. Cotton 10. Plastic is used in electric wires because it is …………………………………

a. light, strong and durable.

b. non-biodegradable.

c. non-reactive.

d. poor conductor of heat and electricity.

11. Which Rs of the 4R principle does the image depict? (Choose more than one option.)

a. Recycle

b. Reduce

c. Recover

d. Reuse

12. Firemen’s uniform is made using ……………………… material.

a. teflon

b. special plasticware

c. melamine coated synthetic

d. bakelite coated synthetic

13. Sam would need a ………….. rope for a mountaineering expedition.

a. cotton

b. jute

c. nylon

d. silk

14. ……………… material is commonly used for making kitchen containers. a. PVC

b. Acrylic c. Teflon d. PET

15. ………………. is commonly used for making parachute ropes. a. Polyethene

b. Nylon c. Silk

d. Polyester 16. Shawls and sweaters are made using …………………… synthetic polymer

as a substitute for wool. a. nylon

b. terylene c. polyester d. acrylic

17. During long distance travel, you will like to take drinking water in a bottle

made of ……………………. a. rayon. b. glass.

c. leather. d. plastic.

18. The fibre that burns readily emitting the smell of burning paper is ……………

a. cotton. b. rayon. c. polyester.

d. acrylic.

19. Which of these products is made by using only man-made substances?

i ii

a. i. b. ii.

c. Both i. and ii. d. None of these.

20. ……………………. contribute to environmental pollution.

a. Cotton clothes b. Plastic bags

c. Woollen clothes d. Paper

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