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.]
# q9 H0 A7 v! {; _1 ?; d+ n3 i, r
$ g: [, ]7 g; Y1 F
! C8 |  z! Z' v, `so far what I have done is used the equation for GPE
% Q+ F, t' W% p- Zwhich is
7 b8 \' I- T  ~5 yU = - (G me m) / r

7 Q* L" G. I6 X7 Dwhere G is 6.674e-11 Nmkg-2
; }* p4 }* d6 `3 n. Jme is the mass of the planet 5.1e24 kg
m is the mass of the space ship 5.9e4 kg
r 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

* |6 T4 B9 h) B5 F
% W; v$ |( x# W# c用这个公式错了么?
还是说只是纯粹的计算出错?

chulinlong

3# Maths
" w1 y3 c; N& a: r( T5 x( G
+ @% f% q0 q  }) E+ M6 d' j
9 K& g; o! `5 o, Y这个公式对的