Consider a spherical planet of uniform density p. The distance from the planet's center to its surface (i.e., the planet's radius) is R_p. An object is located a distance R from the center of the planet, where R < R_p. (The object is located inside of the planet.)(adsbygoogle = window.adsbygoogle || []).push({});

Find an expression for the magnitude of the acceleration due to gravity, g(R), inside the planet.

density p = Me / Ve

where Me = (gR^2)/G and Ve = (4/3)piR^3

From the above equations, we try plug everything into the density equation and solve for g. My calculation is

p = ((gR^2)/G)/(4/3)piR^3 and solving for g, I get

g(R) = (4/3)p(pi^2)R(G)

and Rewrite your g(R) in terms of g(p), the gravitational acceleration at the surface of the planet, times a function of R.

I have the first part of the question, but I am not sure how to approach the second part by rewriting g(R) in terms of g(p)

Thank you

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# Homework Help: Gravitational Acceleration inside a Planet

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