## Fundamentals of Physics Extended (10th Edition)

Since gravitational potential energy is U = mgd, then as the diver falls, the difference in his potential energy would be $\Delta U = mg\Delta d$. The change in his position over time is his velocity, which we are told is 59 m/s. Therefore the potential energy is decreased by 39318 Joules/second Since he is traveling at terminal speed, his velocity will not continue to increase and therefore his KE will also stay constant. Since mechanical energy is Potential Energy + Kinetic Energy, then his Mechanical Energy will decrease by 39318 Joules/second