Two small and heavy spheres, each of mass M, are placed a distance r apart on a horizontal surface. The graviational potential at the mid-point on the line joining the centre of the spheres is :-

Options

A. zero
B. `(Gm^(2))/(r^(2))`
C. `(Gm^(2))/(2r^(2))`
D. `(Gm^(2))/(4r^(2))`

Answer

a

Explanation

`E=+(Gm^(2))/(((r)/(2))^(2))-(Gm^(2))/(((r)/(2))^(2))`
`=(4Gm^(2))/(r^(2))-(4Gm^(2))/(r^(2))`
`E=0.`