Q. In a solar system, the time-period of revolution of a planet tracing a circular orbit of radius R is proportional to:
A) $R^3$
B) $R^{1/2}$
C) $R^{3/2}$
D) $R^2$
Explanation
[Solution from source] For a circular orbit $GMm/R^2=m(2\pi/T)^2R$, so $T^2=4\pi^2R^3/(GM)$ and $T\propto R^{3/2}$ (Kepler's third law). Answer (3).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.