Practicing Success
A satellite with kinetic energy E is revolving round the earth in a circular orbit. The minimum additional kinetic energy required for it to escape to outer space is |
$\sqrt{2} E$ 3E $\frac{E}{\sqrt{2}}$ E |
E |
$\frac{GMm}{r^2}=\frac{mv_0^2}{r}$ $v_0=\sqrt{\frac{GM}{r}} ; v_{e}=\sqrt{\frac{2 GM}{r}}$ orbital KE = $\frac{1}{2} mv_0^2$ $=\frac{1}{2} m \frac{GM}{r}$ KE of escape = $\frac{1}{2} mv_0^2$ $=\frac{1}{2} m\left(\frac{2 GM}{r}\right)=\frac{GMm}{r}=2 E$ Additional KE required = 2E – E = E |