Q. Two particles each of mass $m$ are moving around a circle of radius $R$ due to their mutual gravitational force of attraction, velocity of each particle is
A) $v = \sqrt{\frac{Gm}{2R}}$
B) $v = \sqrt{\frac{Gm}{R}}$
C) $v = \sqrt{\frac{Gm}{4R}}$
D) None of these
Explanation
(c) Here the force of attraction between them provides the necessary centripetal force
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$\therefore\ \frac{mv^{2}}{R} = \frac{Gm^{2}}{(4R)^{2}}$
$\therefore\ v = \sqrt{\frac{Gm}{4R}}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.