Tiêu đề Friction (T or Q ) E.pdf ✅

PHYSICS Q.1 It is difficult to run on the sand since no frictional force is produced by sand. Ans. [False] Q.2 It is unreasonable to expect the coefficient of friction to be more than unity. Ans. [False] Q.3 The direction of the force of friction always opposes the tendency of relative motion of a body. Ans. [True] Q.4 When a person walks on a rough surface, the frictional force exerted by the surface on the person is opposite to the direction of his motion. Ans. [False]