Question

State and explain Kepler’s law for planetary motion.

Answer 1

I Law : 

Every planet moves in an elliptical orbit around the sun with sun at one of the focus.

II Law: 

The line joining the planet to the sun sweeps out equal areas in equal interval of time.

III Law: 

The square of the period of any planet about the sun is proportional to the cube of the semi-major axis of the ellipse.