A 0.32-kg stone is held 1.1 m above the top edge of a water well and then dropped into it. The well has a depth of 4.9 m.
(a) Taking
y = 0
at the top edge of the well, what is the gravitational potential energy of the stone–Earth system before the stone is released?
J

(b) Taking
y = 0
at the top edge of the well, what is the gravitational potential energy of the stone–Earth system when it reaches the bottom of the well?
J

(c) What is the change in gravitational potential energy of the system from release to reaching the bottom of the well?
J