Friction is everywhere! It is the force that slows down moving objects and helps us walk. Chapter 9 of Class 8 Science from NCERT book deals with friction in detail. You would learn in detail about why friction occurs and how it affects motion. You’ll also learn about types of friction like static, sliding, rolling, and fluid friction. The chapter also has benefits and downsides of friction with real-life examples.
This set of MCQs and match-the-following questions is going to help you revise the different topics from Chapter 9. Concepts like reducing friction with lubricants and increasing grip with rough surfaces are dealt with in detail. Solving these questions will help you in making your understanding sharper and revision faster.
Class 8 Science Chapter 9 MCQ Online Test Questions and Answers
Question 1. What does friction do to motion?
a) Stops motion
b) Speeds up motion
c) Opposes motion
d) Has no effect on motion
Answer:
c) Opposes motion
Question 2. What causes a moving object to eventually stop?
a) Gravitational force
b) Frictional force
c) Magnetic force
d) Muscular force
Answer:
b) Frictional force
Question 3. What is friction caused by?
a) Magnetic fields
b) Surface irregularities
c) Gravitational pull
d) Electrostatic forces
Answer:
b) Surface irregularities
Question 4. What happens when friction is reduced?
a) Motion becomes smoother
b) Objects stop faster
c) Force requirement increases
d) Energy loss increases
Answer:
a) Motion becomes smoother
Question 5. What does sprinkling powder on a carrom board do?
a) Increases friction
b) Reduces friction
c) Has no effect
d) Stops motion completely
Answer:
b) Reduces friction
Question 6. What happens to friction when surfaces are pressed harder?
a) Friction increases
b) Friction decreases
c) Friction remains the same
d) Friction disappears
Answer:
a) Friction increases
Question 7. Why do gymnasts apply a coarse substance to their hands?
a) To reduce weight
b) To increase grip
c) To decrease friction
d) To cool their hands
Answer:
b) To increase grip
Question 8. Which type of friction is the highest?
a) Static friction
b) Sliding friction
c) Rolling friction
d) Fluid friction
Answer:
a) Static friction
Question 9. Which friction comes into play when an object starts moving?
a) Rolling friction
b) Static friction
c) Sliding friction
d) Fluid friction
Answer:
b) Static friction
Question 10. What is the purpose of grooved soles in shoes?
a) To look good
b) To reduce weight
c) To increase friction
d) To make shoes waterproof
Answer:
c) To increase friction
Question 11. What happens when a matchstick is struck on a rough surface?
a) It bends
b) It catches fire
c) It cools down
d) It stops working
Answer:
b) It catches fire
Question 12. What reduces friction in machines?
a) Oil and grease
b) Water
c) Air pressure
d) Increased weight
Answer:
a) Oil and grease
Question 13. What type of friction acts on an airplane in flight?
a) Rolling friction
b) Sliding friction
c) Fluid friction
d) Static friction
Answer:
c) Fluid friction
Question 14. Why do car tires have treads?
a) To reduce weight
b) To increase friction
c) To decrease speed
d) To improve appearance
Answer:
b) To increase friction
Question 15. Which friction is the smallest?
a) Static friction
b) Sliding friction
c) Rolling friction
d) Fluid friction
Answer:
c) Rolling friction
Question 16. What does friction produce?
a) Heat
b) Light
c) Sound
d) Magnetic force
Answer:
a) Heat
Question 17. What is the common name for gases and liquids in terms of friction?
a) Solids
b) Fluids
c) Lubricants
d) Viscous substances
Answer:
b) Fluids
Question 18. What is drag?
a) Friction in fluids
b) Magnetic pull
c) Gravitational force
d) Heat loss
Answer:
a) Friction in fluids
Question 19. What happens when you rub your palms together?
a) They cool down
b) They become warm
c) They generate light
d) They become slippery
Answer:
b) They become warm
Question 20. What happens when the surface of a carrom board is rough?
a) Friction increases
b) Friction decreases
c) Motion becomes smoother
d) Friction disappears
Answer:
a) Friction increases
Question 21. What are lubricants used for?
a) To increase weight
b) To reduce friction
c) To absorb heat
d) To increase pressure
Answer:
b) To reduce friction
Question 22. Why do vehicles use ball bearings?
a) To increase speed
b) To reduce rolling friction
c) To increase friction
d) To decrease weight
Answer:
b) To reduce rolling friction
Question 23. Why do gymnasts rub their hands with coarse powder?
a) To cool their hands
b) To improve grip
c) To reduce friction
d) To protect their skin
Answer:
b) To improve grip
Question 24. Why are airplanes given streamlined shapes?
a) To increase speed
b) To reduce fluid friction
c) To increase weight
d) To improve stability
Answer:
b) To reduce fluid friction
Question 25. What type of friction acts when a bicycle wheel rolls on the road?
a) Sliding friction
b) Rolling friction
c) Static friction
d) Fluid friction
Answer:
b) Rolling friction
Question 26. What does oil between moving parts of a machine do?
a) Reduces pressure
b) Reduces friction
c) Increases weight
d) Increases friction
Answer:
b) Reduces friction
Question 27. What is the primary cause of friction?
a) Weight of an object
b) Irregularities of surfaces in contact
c) Gravitational pull
d) Speed of motion
Answer:
b) Irregularities of surfaces in contact
Question 28. What happens to friction when a heavy object is pressed harder against a surface?
a) Friction increases
b) Friction decreases
c) Friction disappears
d) Friction remains constant
Answer:
a) Friction increases
Question 29. What type of friction acts when an object is at rest?
a) Sliding friction
b) Static friction
c) Rolling friction
d) Fluid friction
Answer:
b) Static friction
Question 30. What reduces friction in liquids and gases?
a) Smooth surfaces
b) Streamlined shapes
c) Increased weight
d) Increased speed
Answer:
b) Streamlined shapes
Question 31. Why do kabaddi players rub their hands with soil?
a) To cool their hands
b) To increase grip
c) To reduce sweat
d) To decrease friction
Answer:
b) To increase grip
Question 32. What is the effect of rolling friction compared to sliding friction?
a) Rolling friction is higher
b) Rolling friction is lower
c) Both are equal
d) Rolling friction does not exist
Answer:
b) Rolling friction is lower
Question 33. What happens to energy when friction acts on a moving object?
a) It is lost as heat
b) It is stored
c) It increases motion
d) It remains constant
Answer:
a) It is lost as heat
Question 34 – Match the Following
| Column A | Column B |
|---|---|
| 1. Friction between fluids and objects | A. Ball bearings |
| 2. Device used to reduce rolling friction | B. Drag |
| 3. Substance used to reduce friction | C. Static friction |
| 4. Friction that prevents motion | D. Lubricant |
| 5. Friction in liquids and gases | E. Rolling friction |
Answer:
| Column A | Correct Answer |
|---|---|
| 1. Friction between fluids and objects | B. Drag |
| 2. Device used to reduce rolling friction | A. Ball bearings |
| 3. Substance used to reduce friction | D. Lubricant |
| 4. Friction that prevents motion | C. Static friction |
| 5. Friction in liquids and gases | B. Drag |
