Q 11-07-003NEETNEET 2026Top questionEasy
In a solar system, the time-period of revolution of a planet tracing a circular orbit of radius $R$ is proportional to :
Answer: (B) $R^{3/2}$
Concept. Gravity supplies the centripetal force.
Step 1. Equation.
$$\frac{GMm}{R^2} = m\frac{4\pi^2}{T^2}R \;\Rightarrow\; T^2 = \frac{4\pi^2}{GM}R^3$$
Step 2. Result. $T \propto R^{3/2}$.
Answer. $R^{3/2}$ (Option B).
Solution by Sreeraj P, M.Sc Physics