Q 11-07-042JEE MainJEE Main 2026 (4 Apr, Shift 2)Easy
The height in terms of radius of the earth $(R)$, at which the acceleration due to gravity becomes $\dfrac{g}{9}$, where $g$ is acceleration due to gravity on earth's surface, is ______.
Answer: (C) $2R$
$g_h = g\left(\dfrac{R}{R + h}\right)^2 = \dfrac{g}{9} \Rightarrow \dfrac{R}{R + h} = \dfrac{1}{3} \Rightarrow h = 2R$.
Solution by Sreeraj P, M.Sc Physics