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]
$ S' ^5 w, ~7 O+ p# g+ _
[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]
1 V" |9 G% |: V( `" {
/ p0 f: o3 A7 D  W; G* Y
+ g3 S$ O4 K3 m! B, [% K8 cso far what I have done is used the equation for GPE
which is
U = - (G me m) / r

where G is 6.674e-11 Nmkg-2
me is the mass of the planet 5.1e24 kg
m is the mass of the space ship 5.9e4 kg
7 _8 W9 n+ p6 o1 K4 z$ Zr 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

5 s* W# ~* h- B! l$ }
用这个公式错了么?
7 l7 T  d' V% s' x% f2 U还是说只是纯粹的计算出错?

chulinlong

3# Maths

2 q: K8 W* g# z$ {1 R
这个公式对的