If the moon were half as far from the earth as it is now, the gravitational force it exerts on the earth would be
A) one-quarter its present value.
B) half its present value.
C) twice its present value.
D) four times its present value.

Question

Quizplus · Accepted Answer

The gravitational force between two objects is inversely proportional to the square of the distance between them. If the distance is halved, the gravitational force becomes (1/0.5)^2 = 4 times its original value.

If the Moon Were Half as Far from the Earth