The gravitational potential strictly at the center of a solid, uniform Earth of mass M and radius R is: MCQ with Answer and Explanation

The gravitational potential strictly at the center of a solid, uniform Earth of mass M and radius R is:

A. -3GM / 2R

B. -GM / 2R

C. Zero

D. -GM / R

Answer: Option A

Solution (By JKExamLibrary)

The gravitational potential V inside a uniform solid sphere at a distance r from the center is V = -GM * (3R^2 - r^2) / (2R^3). At the exact center of the Earth, r = 0. Substituting r = 0 gives V = -GM(3R^2) / 2R^3 = -3GM / 2R. The potential is strictly non-zero and highly negative.

This question belongs to: Science Physics

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