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 surface

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

Correct Answer: Option B

B. 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.

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