A woman stands on the edge of a cliff and throws a stone vertically downward with an initial speed of 10 m/s. The instant before the stone hits the ground below, it has 450 J of kinetic energy. If she were to throw the stone horizontally outward from the cliff with the same initial speed of 10 m/s, how much kinetic energy would it have just before it hits the ground?
A)50 J
B)100 J
C)450 J
D)800 J
E)950 J

Question

Quizplus · Accepted Answer

The kinetic energy of the stone just before it hits the ground depends only on its speed at that instant, not on the direction of its initial velocity. Since the stone is thrown with the same initial speed in both scenarios, it will have the same kinetic energy of 450 J just before hitting the ground.

A Woman Stands on the Edge of a Cliff and Throws