Question 218: Gravitation

Question

Average density of the earth

Accepted Answer

Mass of earth = Volume $$ 	imes $$ Density of earth($$ho$$)
$$	herefore$$ M = $${{4 \over 3}\pi {R^3}} $$$$ 	imes $$ $$ho $$
We know, $$g = {{GM} \over {{R^2}}}$$
$$ \Rightarrow g = {{G 	imes ho  	imes {4 \over 3}\pi {R^3}} \over {{R^2}}}$$
$$ \Rightarrow $$ $$g = {4 \over 3}ho \pi GR$$
$$	herefore$$ $$g \propto ho $$ or $$ho \propto g$$

Answer

is a complex function of $$g$$

Answer

does not depend on $$g$$

Answer

is inversely proportional to $$g$$

Answer

is directly proportional to $$g$$

Gravitation

Average density of the earth

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