Question

What is the cause of friction? explain.

Answer 1

Causes of Friction. Friction is a force that resists the relative motion between two objects or materials. The causes of this resistive force are molecular adhesion, surface roughness, and deformations. Adhesion is the molecular force resulting when two materials are brought into close contact with each other.

Answer 2

Cause of friction :-
1 Old view:- according to it all the surfaces however smooth they are they have irregularities in the form of hills and valleys.
When 1 such surface tries to move over another then interlocking takes place.
To overcome these interlocking an excess force is required.
2. Modern view:- when 1 surface is in contact with another the intermolecular takes place.
To overcome these intermolecular an excess force is required which is called friction.

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