What happens to the gravitation force between two objects that are 15 m apart, when one of them moves 3 m closer?

It decreases by a factor of 1 9/16.

It decreases by a factor of 1 1/4.

It increases by a factor of 1 9/16.

It increases by a factor of 1 1/4.***

1 answer

Since F=Gmm/r^2,
r becomes 4/5 r, so F grows by a factor of (5/4)^2 = 26/16 = 1 9/16