Question

If Earth were twice as far from the sun, the force of gravity attracting the Earth to the Sun would be

a. twice as strong

b. half as strong

c. one-quarter as strong.

Answer 1

The strength of the gravitational forces between two objects is
inversely proportional to the SQUARE of the distance between them.

So when the distance changes from ' D ' to ' 2D ', the strength of the
gravitational forces changes from ' F ' to

(1/2)² F = 1/4 F .