Question

Two point objects with different masses are kept at a distance $R$ apart from each other. If the gravitational force between them is $F$, then:

• A. $F\propto R^2$
• B. $F\propto R^4$
• C. $F\propto \frac{1}{R^2}$
• D. $F\propto \frac{1}{R^4}$

Answer 1

The correct option is C

$F\propto \frac{1}{R^2}$

According to the Universal law of gravitation, the gravitational force between two bodies is directly proportional to product of their masses and inversely proportional to the square of the distance between them. Thus, in this case, the gravitational force between the point masses is inversely proportional to $R^2$.
Hence, $F\propto \frac{1}{R^2}$