Asked by Tushar Puranik | 26th Nov, 2013, 08:36: AM

Expert Answer:

The cause of sliding friction is the minute roughness of the two surfaces sliding over each other.
Ideally two smooth surfaces appear smooth only from outside, but if one sees through a microscope, then there are few uneven grooves on the surface. This causes the friction between the two surfaces.
Kindly ask separate questions as separate queries.

Answered by Romal Bhansali | 26th Nov, 2013, 10:05: AM

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