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.]
2 j# m, ?2 I( o  ^

; G; m) w. [" K  Q( I8 u0 Zso far what I have done is used the equation for GPE
2 k1 N3 s9 K' ]7 iwhich is
U = - (G me m) / r
: w" P8 K: S$ y
where G is 6.674e-11 Nmkg-2
8 Z( w0 Y, `: _) X: U6 Lme is the mass of the planet 5.1e24 kg
5 [  c/ Z6 ^0 E7 S, L- hm 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

用这个公式错了么?
( c8 h4 O/ w& B/ G/ v' B7 G" A. {5 V还是说只是纯粹的计算出错?

chulinlong

3# Maths
' W' T8 G! ?2 s0 [, L

) |+ [$ i, H" U这个公式对的