A shotput player throws a shotput of mass 3 kg. If it crosses the top of wall 2 m high at a speed of 4 ms-1. Compute the total mechanical energy gained by the shotput when it crosses the wall.
(Given, g = 9.8 ${{ms}^{-2}}$)
Given, m = 3 kg
h = 2m
v = 4 ${{ms}^{-1}}$ , g = 9.8 ${{ms}^{-2}}$
Total mechanical energy = KE + PE =1/2 m${{v}^{2}}$
= 1/2 x 3 x 16 + 3 x 9.8 x 2 = 24+58.8 = 82.8 J