Question

One of your summer lunar space camp activities is to launch a 1070 kg rocket from the surface of the Moon. You are a serious space camper and you launch a serious rocket: it reaches an altitude of 231 km. What gain AU in gravitational potential energy does the launch accomplish? The mass and radius of the Moon are 7.36 x 1022 kg and 1740 km, respectively. AU = 2.665 x1015 J Incorrect

Answer 1

given

distance

r1 = 1740000 m

r2 = (1740+231) = 1971 km = 1971000 m

change in potential energy

$\Delta U$ = Gm1m2(1/r1-1/r2)

$\Delta U$ = 6.65*10^-11*7.36*10^22*1070(1/1740000-1/1971000) = 3.527*10^8 J