question_answer

Two bodies of masses m and 4 m are placed at a distance r. The gravitational potential at a point on the line joining them where the gravitational field is zero is   AIEEE  Solved  Paper-2011

A) \[-\frac{9Gm}{r}\]                              

B)  Zero

C) \[-\frac{4Gm}{r}\]                              

D)  \[-\frac{6Gm}{r}\]

Correct Answer: A

Solution :

             Field is zero at O.               \[V=-\frac{GM}{r/3}-\frac{4GM}{2r/3}\]    \[=-\frac{9GM}{r}\]