Explain why two surfaces in contact with each other experience frictional force.

Explanation

Two surfaces in contact with each other experience frictional force due to irregularities on their surfaces. When two surfaces come in contact with eah other, these irregularities present on the surfaces of these objects interlock with each other. When one of these surfaces moves or tries to move with respect to the other surfaces, the interlocks between the surfaces resist this motion. This resistance gives rise to friction.