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.]

( F# Q" ]; ~; c& y  n
so far what I have done is used the equation for GPE
which is
U = - (G me m) / r

' b0 ^8 b- B2 Y2 v( E7 A# Pwhere G is 6.674e-11 Nmkg-2
: Y! n: o( c% e4 z% Q% ?me is the mass of the planet 5.1e24 kg
4 A* j6 o4 E1 y7 V' |9 Q) Hm is the mass of the space ship 5.9e4 kg
0 P9 Q# }* F1 {; xr 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

, g+ b0 w2 i4 d- X& w. V
用这个公式错了么?
9 z1 J2 X4 E- E8 v还是说只是纯粹的计算出错?

chulinlong

3# Maths
  ^. i- ]9 t$ W% H1 H$ n
- ]9 [9 c! P2 h% B- i  i. ?' P
这个公式对的