Questions :-

1. Friction is an example of ___________
(a) Contact force
(b) Non – contact force
(c) Both of these
(d) None of these

2. The direction of force of friction is always ______________ to the direction of motion.
(a) Same
(b) Opposite
(c) Unchanged
(d) None of these

3. When one body rolls over the surface of another body, the resistance to its motion is called ____________
(a) Rolling friction
(b) Sliding friction
(c) Fluid friction
(d) Static friction

4. Which of these characteristics does a smooth surface has?
(a) Less frictional force
(b) More frictional force
(c) Sometimes less and sometimes more force
(d) All of the above

5. When a body slides over the surface of another body, the resistance to its motion is called ______________
(a) Rolling friction
(b) Sliding friction
(c) Fluid friction
(d) Static friction

6. Fluid friction is also known as ___________
(a) Rolling friction
(b) Sliding friction
(c) Drag
(d) Static friction

7. Lubricants are the substance which ____________ friction.
(a) Increases
(b) Decreases
(c) Increase or decrease
(d) None of these

8. Fluids are ___________
(a) Gas
(b) Liquid
(c) Gas as well as liquid
(d) None of these

9. Sliding friction is __________ than static friction.
(a) Smaller
(b) Greater
(c) Smaller as well as greater
(d) None of these

10. Rolling friction is __________ than sliding friction.
(a) Smaller
(b) Greater
(c) Smaller as well as greater
(d) None of these