Question

Find an expression for the square of the orbital period.

Answer 1

T²= 4π²R³/GM

Step-by-step explanation:

First we know that

Fg= Fc

Because centripetal force must equal gravitational force

So

GMm/R² = Mv²/R

But velocity is 2πR/T

So by substitution we have

GMm/R²= M (2πR/T)/T

We have

T²= 4π²R³/GM as period