Q. An artificial satellite moving in circle orbit around the earth has a total (kinetic + potential) energy $E_{0}$. Its potential energy and kinetic energy respectively are
A) $2E_{0}$ and $- 2E_{0}$
B) $- 2E_{0}$ and $- 3E_{0}$
C) $2E_{0}$ and $- E_{0}$
D) $- 2E_{0}$ and $- E_{0}$
Explanation
(c) $KE\ = \frac{GMm}{2r} = - E_{0}$, and
$PE = - \frac{GMm}{r} = 2E_{0}$
$\Rightarrow \ TE = KE + PE = - \frac{GMm}{2r} = E_{0}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.