kinetic energy = 1/2 m v^2
m= mass = 66 kg
h= height = 4.9 m
v = speed = 6.70 m/s
KE = 1/2 (66) (6.7)^2 = 1,481.37 J
PE = potential energy = m g h
g = gravity = 9.8 m/s^2
PE = 66 (9.8) (4.90) = 3,169.32 J
When he hits the water potential energy is converted into kinetic energy:
E = KE + PE = 1,481.37 + 3,169.32 = 4,650.69 J
Answer: 4,650.69 J
