Friction arises due to the interlocking of depressions and__________present in a body.pls fill in the blank.
The answer is elevations or ridges in the body . when a body slides over another, a force exists which opposes their motion. This is the force of friction.
It arises due to the fact that though the surfaces may be planed and smoothed but there are depressions and ridges on the surfaces which interlock and hence oppose the relative motion as shown in the diagram.