For two satellites at distances R and 7R above the earth's surface, the ratio of their

Distances of the two satellites from the centre of the earth are r1 = 2R and r2 = 8R, respectively (R = earth's radius. Their potential energies are            V1=−GmMr1 and V2=−GmMr2Their ratio is V1V2=r2r1=8R2R=4The kinetic energy of a satellite can be obtained from the relation          mv2r=GmMr2or      K=12mv2=GmM2r          K1=GmM2r1 and K2=GmM2r2The ratio of their kinetic energies is       K1K2=r2r1=8R2R=4Their total energies are E1=−GmMr1+GmM2r1=−GmM2r1and   E2=−GmMr2+GmM2r2=−GmM2r2Their ratio is E1E2=r2r1=8R2R=4Hence, the correct choices are (2), (3) and (4).