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]
7 Q" }0 A$ a7 Z9 m/ l% s* M  r
[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]


so far what I have done is used the equation for GPE
which is
U = - (G me m) / r
$ M. g9 B/ F0 w% k6 q, N6 X; ^
) I+ J& p" z0 W9 v2 rwhere 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
& f7 \3 O: z& x0 `2 I4 l5 Ir 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

+ {% |# @! D  y
8 C2 f" {& Y) L7 D5 ~6 c% Z用这个公式错了么?
  q" y/ c) p& B/ ^' `, G还是说只是纯粹的计算出错?

chulinlong

3# Maths

7 Y; B" N  z- J0 J) {8 [. R
) s4 b3 Q4 D5 W3 ?( _. N这个公式对的