An adult exerts a horizontal force on a swing that is suspended by a rope of length L, holding it at an angle θ with the vertical. The child in the swing has a weight W and dimensions that are negligible compared to L. The weights of the rope and of the seat are negligible. In terms of W and θ, determine
(a) The tension in the rope
(b) The horizontal force exerted by the adult.
(c) The adult releases the swing from rest. In terms of W and θ determine the tension in the rope as the swing passes through its lowest point