Q. The gravitational potential energy magnitude of a body at a distance $r$ from the centre of Earth is $U$. The weight of the body at that point is :

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A

$U r$

B

$\frac{U}{r}$

C

$U r^{2}$

D

$U r^{3}$

Solution:

As $U=-G M m / r$ and weight is $W=G M m / r^{2}$ so option (B) is correct.

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