Question

Newton’s law of universal gravitation.. . a.. is equivalent to Kepler’s first law of planetary motion.. b.. can be used to derive Kepler’s third law of planetary motion.. c.. can be used to disprove Kepler’s laws of planetary motion.. d.. does not apply to Kepler’s laws of planetary motion.

Answer 1

By the help of newtons law of gravitation we can derive keplers third law of planetary motion.

Answer 2

Answer:

b.. can be used to derive Kepler’s third law of planetary motion..

Explanation:

As per Newton's law of gravitation we can say that two masses separated by some distance "r" will attract each other with force given by

$F = \frac{Gm_1m_2}{r^2}$

now we can say that

if all planets revolves around the sun in approx circular orbit then the centripetal force on the planets will be due to gravitational force of Sun

so we can say

$\frac{mv^2}{R} = \frac{GMm}{R^2}$

so by solving above equation we can find average orbital speed of all planets and hence we can derive all Kepler's law

so correct answer will be

b.. can be used to derive Kepler’s third law of planetary motion..