Question
Two planets have the same average density but their radii are ${R_1}$ and ${R_2}$. If acceleration due to gravity on these planets be ${g_1}$ and ${g_2}$ respectively, then
✓
Answer
(a)$g = \frac{4}{3}\pi \rho GR$. If $\rho $ = constant then $\frac{{{g_1}}}{{{g_2}}} = \frac{{{R_1}}}{{{R_2}}}$
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