Question

The rope of a swing is 3.2 m long. Calculate the angle from the vertical at which a 95-kg man must begin to swing in order to have the same kinetic energy at the bottom as a 1500-kg car moving at 1.07 m/s (2.39 mi/hr).

Answer 1

Ke car = (1/2) m v^2

potential energy at top of swing = kinetic energy at bottom of swing

m g h = m g L (1-cos theta)

so
(1/2)(1500)(1.07)^2 = 95 * 9.8 * (1 - cos T)
solve for T

Answer 2

30