I'm new to brainy, but here is my question.
andre, whose mass is 77.1 kg, sits on a diving board above a dunk tank. if he is sitting 0.90 m above the water, what is his total mechanical energy?

680 J

Explanation:

Andre's mechanical energy is given by:

where

K is the kinetic energy

U is the gravitational potential energy

The kinetic energy in this case is zero, because Andre is sitting, so its speed is zero: v=0, and the kinetic energy is

The gravitational potential energy is instead

So, the total mechanical energy is