Question

Consider two uniform spheres $S_1$ and $S_2$ of equal masses and radii $r$ and $\frac{r}{2}$ respectively. Gravitational force due to $S_1$ and $S_2$ on a mass at a distance $R$ from their centres is $G_1$ and $G_2$ respectively.

Which of the following is/are correct.

• A.
• B.
• C.
• D.

Answer 1

The correct option is C

Two bodies are uniform spheres, so it can be assumed that their masses are concentrated at a point located at the centre of the spheres. (Spheres can be assumed as point masses without affecting the gravitational force due to them.)

Since the point masses (equal mass) at the centres are located at the same distance from the given mass, the gravitational force on the is the same.

$G_1=G_2$