Question 5
A pile driver drives a pile into the ground by dropping a heavy hammer onto it. How can the blow be made harder?
The right answer is the one marked above.
Raise it to a greater height before releasing it. The higher the hammer is raised, the more potential energy it stores, so the more kinetic energy it carries when it strikes.
Neither the pile driver nor the sledgehammer has a power dial. Height is the setting on both, and that is m g h being used as a control.