Question

Universal gravitational constant $G$ is proportional to distance $r$ between two masses as-

• A. $r^2$
• B. $r$
• C. $1/r$
• D. does not depend upon $r$

Answer 1

The correct option is D does not depend upon $r$

According to Newton's Law of gravitation, the gravitational force between two bodies of mass $M$ and $m$ separated by a distance $r$, is directly proportional to the product of the masses of the objects ( $F\propto Mm$) and inversely proportional to the square of distance between them $F\propto \frac{1}{r^2}$.

When we combine this information, we get

$F\propto \frac{Mm}{r^2}$

$F=G\frac{Mm}{r^2}$

where $G$ is the proportionality constant, called the Universal Gravitational constant.

Since $G$ is a constant it does not depend on $r$.