Question

According to one of the Kepler's laws of planetary motion :

(a) r² ∝ T³
(b) r ∝ T²
(c) r³ ∝ T²
(d) $r^3\propto \frac{1}{T^2}$

Answer 1

(c) r³ ∝ T²
According to Kepler’s third law of planetary motion, the cube of mean distance of a planet from the sun is directly proportional to the square of time it takes to move around the sun.