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Average density of the earth

1. is a complex function of g
2. does not depend on g
3. is inversely proportional to g
4. is directly proportional to g

Correct answer: is directly proportional to g

Solution

Since g = GM/R^2 = G(4/3 pi R^3 rho)/R^2 = (4/3) pi G R rho, the average density rho is directly proportional to g (for fixed R).

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