(2) Now assume that the Earth orbits the sun at the distance of Pluto,
from the sun. What would the gravitational force be in this case?
Removing Earth to the orbit of Pluto changes the radius between the objects, so the force is now , on the order of a thousand times smaller than the force between the Earth in its proper orbit and the sun. Note that as the objects become farther apart, the gravitational force between them drops off as the square of the radius. Laws that have this property are said to obey an inverse square law.
