A 2.00-kg ball has zero potential and kinetic energy.Maria drops the ball into a 20.0-m deep well.After the ball comes to a stop in the mud,the sum of its potential and kinetic energy is:

Question

Quizplus · Accepted Answer

The total energy of the ball is conserved, so the sum of its potential and kinetic energy is the same before and after it is dropped. Before it is dropped, the ball has zero potential and kinetic energy. After it comes to a stop in the mud, it has only potential energy, which is equal to its weight times the height of the well. Therefore, the sum of its potential and kinetic energy is:PE = mgh = (2.00 kg)(9.8 m/s^2)(20.0 m) = 392 JThe negative sign indicates that the energy is potential energy.

A 200-Kg Ball Has Zero Potential and Kinetic Energy