A particle of mass $$M$$ is situated at the centre of a spherical shell of same mass and radius $$a.$$ The gravitational potential at a point situated at $$\frac{a}{2}$$ distance from the centre, will be
A.
$$ - \frac{{3GM}}{a}$$
B.
$$ - \frac{{2GM}}{a}$$
C.
$$ - \frac{{GM}}{a}$$
D.
$$ - \frac{{4GM}}{a}$$
Answer :
$$ - \frac{{3GM}}{a}$$
Solution :
Gravitational potential at point $$\frac{a}{2}$$ distance from centre is given by, $$V = - \frac{{GM}}{a} - \frac{{GM}}{{\frac{a}{2}}} = - \frac{{3GM}}{a}$$
Releted MCQ Question on Basic Physics >> Gravitation
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