Question:
The ratio of the weights of a body on the Earth’s surface to that on the surface of a planet is $9: 4$. The mass of the planet is $\frac{1}{9}$ th of that of the Earth. If ‘ $R$ ‘ is the radius of the Earth, what is the radius of the planet ? (Take the planets to have the same mass density).
$\frac{R}{3}$
$\frac{R}{4}$
$\frac{R}{9}$
$\frac{R}{2}$
Question of from chapter.
JEE Main Previous Year 12 April 2019 II
Correct Option: 4
Solution:
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