Question

a 71kg diver drops from a board 10m above the water surface. use conservation of mechanical energy to find his speed 5m above the water surface.

Answer 1

$E_0=P+K,$

$E_0=mgH,$

$P=mgh,$

$K=\frac{mv^2}2,\implies$

$v=\sqrt{2g(H-h)}=10~\frac ms.$