A stone is dropped from a bridge and allowed to free-fall downward. As it falls a certain distance its gravitational potential energy decreases by 1000J . By how much does the stone's
Kinetic energy increase? (Neglect air resistance).
A) 100J
B) 500J
C) 1000J
D) 2200J

Question

Quizplus · Accepted Answer

According to the law of conservation of energy, the total energy of the system remains constant. Initially, the stone has only gravitational potential energy, and as it falls, this potential energy is converted into kinetic energy. Therefore, the decrease in gravitational potential energy is equal to the increase in kinetic energy. So, the stone's kinetic energy increases by 1000J, which is equal to the decrease in potential energy. Thus, the correct choice is C) 1000J.

A Stone Is Dropped from a Bridge and Allowed to Free-Fall