question_answer

Give reasons for the following. (i) Horse continues to apply force in order to move a cart with constant speed. (ii) Water sprinkler used for grass lawns begins to rotate as soon as water is supplied. (iii) Water drops are removed from wet clothes by giving tight jerk to the cloth.

Answer:

                               (i) The frictional force acts on cart wheel in opposite direction to motion of the cart.    (ii) When water is pushed out of sprinkler with a force, it exerts reaction force on the sprinkler, causing it to rotate.                        (iii) Water drops have inertia of rest. They do not move with the cloth as it is jerked and come out.