Q. Two identical satellites are at $R$ and $7R$ away from earth surface, the wrong statement is ($R =$Radius of earth)
A) Ratio of total energy will be $y$
B) Ratio of kinetic energies will be $y$
C) Ratio of potential energies will be $y$
D) Ratio of total energy will be $y$ but ratio of potential and kinetic energy will be $\mathcal{z}$
Explanation
(d) Orbital radius of satellites $r_{1} = R + R = 2R$
$r_{2} = R + 7R = 8R$
$U_{1} = - \frac{GMm}{r_{1}}$ and $U_{2} = - \frac{GMr}{r_{2}}$
$K_{1} = \frac{GMm}{2r_{1}}$ and $K_{2} = \frac{GMm}{2r_{2}}$
$E_{1} = \frac{GMm}{2r_{1}}$ and $E_{2} = \frac{GMm}{2r_{2}}$
$\therefore\ \frac{U_{1}}{U_{2}} = \frac{K_{1}}{K_{2}} = \frac{E_{1}}{E_{2}} = 4$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.