Q 11-07-147JEE MainJEE Main 2021 (18 Mar, Shift 2)Easy
The angular momentum of a planet of mass $M$ moving around the sun in an elliptical orbit is $\vec L$. The magnitude of the areal velocity of the planet is:
Answer: (D) $\frac{L}{2M}$
In time $dt$ the radius vector sweeps area $dA = \frac12 r\,(v\,dt)\sin\theta$, so $\dfrac{dA}{dt} = \dfrac{rv\sin\theta}{2} = \dfrac{L}{2M}$.
Solution by Sreeraj P, M.Sc Physics