question_answer

When a person walks on a rough surface, the frictional force exerted by the surface on the person is opposite to direction of his motion. State whether it true or false?

Answer:

                False. When a person walks, he pushes the ground backward with his foot. The tendency of the foot when it is in the contact of the earth is to move backward. Hence the force of friction acts in the forward direction, i.e., in a direction in which the man walks.