The minimum energy required to launch a m kg satellite from the Earth's surface in a circular orbit at altitude 2R, where R is the radius of earth is

Total energy, E=12mv2−GmMr=GmM2r−GMmr=−GmM2rr=2R=R=3RE=GmM6R Potential energy =−GMmR Minimum energy required =16GMmR−−GMmR=56GMmR                                             =56mgR