A projectile is fired with speed u making angle θ with the horizontal. Its potential energy at the highest point is
(a) (1/2) mu2 sin2θ
(b) (1/2) mu2 cos2θ
(c) (1/2) mu2
(d) (1/2) mu2 sin22θ
Answer is (a) (1/2) mu2 sin2θ
The vertical component of velocity is reduced to zero and kinetic energy corresponding to it is converted into potential energy.
