Tuesday 29 August 2017

CBSE - Class 8 - Science - Friction (Assignment Sheet) (#cbseNotes)


Class 8 - Physics

Multiple Choice Questions (1-10)

1. It is difficult to walk on any oily floor because
a) Floor gets spoiled
b) There is more resistance
c) Force of friction is high
d) Force of friction is very less

2. Spring balance is a device used for measuring the _____________ acting on an object.
a) mass
b) pressure
c) force
d) None of the above

3. A matchstick struck on a matchbox catches fire easily because
a) Friction may cause fire
b) Of chemical reaction
c) Force heated the match stick
d) None of the above

4. Tyres are treaded to
a) To look good
b) Increase friction
c) To increase its longivity
d) To increase weight of the tyre

5. Lubricants are substances which
a) Increases friction
b) Are used to light fire
c) Reduces friction
d) Are used to put off fire

6. Sliding friction is _________ than / to rolling friction
a) smaller
b) greater
c) equal
d) None of the above

7. The frictional force exerted by fluids is also called ______
a) drug
b) drag
c) drop
d) drown

8. Four children were asked to arrange forces due to rolling, static and sliding frictions in a increasing order. Their arrangements are given below. Choose the correct arrangement.
a) Rolling, Static, Sliding
b) Static, Rolling, Sliding
c) Rolling, sliding, static
d) Sliding, Static, Rolling

9. A boat or an aeroplane has a pointed or tapering front / head. Why?
a) To increase the friction of fluid
b) To reduce the friction of fluid
c) To look good
d) For no reason

10. The sole of the shoes becomes plain after wearing it for several months. The reason is
a) Wearing out due to friction
b) Wearing out due to no friction
c) Sole is of bad quality
d) None of the above

11. What form of energy does friction always produce?

12. Will you be able to walk if there is no friction?

13. Why is talcum powder sprinkled on carrom board?

14. Why are boats and aeroplanes given a special shape?Name the kind of shape also give reason for the same.

15. State two problems caused by friction.

16. Why do sports man use shoes with spikes?

17. Why is oil or grease applied to the moving parts of the machine.

18. Explain the terms:
a) Drag
b) Fluids
c) Rolling friction

1 comment:

We love to hear your thoughts about this post!

Note: only a member of this blog may post a comment.