A uniform spherical shell gradually shrinks maintaining its shape. The gravitational potential at the centre
A.
increases
B.
decreases
C.
remains constant
D.
cannot say
Answer :
increases
Solution :
The gravitational potential at the centre of uniform spherical shell is equal to the gravitational potential at the surface of shell i.e.,
$$V = \frac{{ - GM}}{a},$$ where $$a$$ is radius of spherical shell
Now, if the shell shrinks then its radius decrease then density increases, but mass is constant. so from above expression if a decreases, then $$V$$ increases.
Releted MCQ Question on Basic Physics >> Gravitation
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