Question

If the distance between two masses is tripled, the gravitational force between changes by a factor of

Answer 1

A. 1/9

Explanation:

The gravitational force between two objects is given by

$F=G\frac{m_1 m_2}{r^2}$

where

G is the gravitational constant

m1 and m2 are the two masses

r is the distance between the two masses

From the formula, we see that the magnitude of the force is inversely proportional to the square of the distance: therefore, if the distance is tripled (increased by a factor 3), the magnitude of the force changes by a factor

$\frac{1}{r^2}=\frac{1}{3^2}=\frac{1}{9}$

Answer 2

A. 1/9 is the answer.