1) What is the minimum energy required to launch a satellite of mass m from the surface of a planet of mass M and radius R in a circular orbit at an altitude of 2R? A) $\frac{5GMm}{6R}$ B) $\frac{2GMm}{3R}$ C) $\frac{GMm}{2R}$ D) $\frac{GMm}{3R}$ Answer: Option AExplanation:E= energy of satelite- energy of mass on the surface of plannar $=-\frac{GMm}{2r}-\left(-\frac{GMm}{R}\right)$ Here, r= R+2R= 3R Substituting in about the equation we get, $E= \frac{5GMm}{6R}$
