Assertion (A): A body is lying at rest on a rough horizontal surface. A person accelerating with acceleration \(a\) (where \(a\) is positive constant and \(\hat{i}\) is a unit vector in horizontal direction) observes the body. With respect to him, the block experiences a kinetic friction.
Reason (R): There is relative motion between the block and surface in person's frame of reference.
Solution:
In the accelerating person's non-inertial frame, a pseudo-force acts on the block. If this pseudo-force causes relative motion, kinetic friction acts. A is true. Kinetic friction by definition arises due to relative motion between surfaces. So, R is true and correctly explains A.
Leave a Reply