The limiting frictional force between two surfaces depends on?

I. the normal reaction between the surfaces
II. the area of surface in contact
III. the relative velocity between the surfaces
IV. the nature of the surfaces

A. I only
B. II only
C. III only
D. I & IV only

Correct Answer: Option D

D. I & IV only

Explanation

– Friction depends on the nature of the surfaces in contact
– Solid friction is independent of the area of the surfaces in contact and the relative velocity between the surfaces.