求 一道物理题 12点前

chulinlong

A space craft of mass 5.9×104 kg is in orbit around a planet of 5.1×1024 kg. If the planet can be assumed to be a uniform sphere of radius 5.4×106 m and the space ship is orbit a height of 6.9×105 m above the surface what is the gravitational potential energy of the ship? [G=6.674×10-11 Nm2kg-2]

[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]
& W3 Q7 h0 Q* L6 R( _- Q6 d

so far what I have done is used the equation for GPE
which is
. c' b: x& k9 ?  U% r( C' y$ fU = - (G me m) / r

where G is 6.674e-11 Nmkg-2
me is the mass of the planet 5.1e24 kg
( Q% f0 v) r9 O3 Z, E( Z# x( Nm is the mass of the space ship 5.9e4 kg
$ @' K! ?- i( a4 Z( G" v# J8 Tr is (i think) the radius of the planet (5.4e4 m) added to the height of the space ship is above the planet (6.9e5 m) and then divided it into G me m

chulinlong

做出来了 谢谢

Maths

. z* ~/ ?( _) o# ]7 n+ o  F7 J
用这个公式错了么?
还是说只是纯粹的计算出错?

chulinlong

3# Maths

9 b3 p0 q7 h8 c& y3 b9 B
这个公式对的