Q 11-07-008NEETNEET 2023Top questionMedium
Two bodies of mass $m$ and $9m$ are placed at a distance $R$. The gravitational potential on the line joining the bodies where the gravitational field equals zero, will be ($G$ = gravitational constant) :
Answer: (C) $-\dfrac{16Gm}{R}$
Concept. Find the null point from equal fields, then add potentials.
Step 1. Null point. $\dfrac{m}{x^2} = \dfrac{9m}{(R - x)^2} \Rightarrow x = \dfrac R4$ from $m$.
Step 2. Potential.
$$V = -\frac{Gm}{R/4} - \frac{9Gm}{3R/4} = -\frac{16Gm}{R}$$
Answer. $-\dfrac{16Gm}{R}$ (Option C).
Solution by Sreeraj P, M.Sc Physics