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]
3 p3 W: j7 {& _: q
[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]
  @& [/ J! x0 g: [$ ?7 o

" J. m, W" ]& ~6 Jso far what I have done is used the equation for GPE
" E( Q( r) D& b" pwhich is
U = - (G me m) / r

( `/ E) S, Q, M/ F# fwhere G is 6.674e-11 Nmkg-2
* m/ T9 ?1 X4 ^" b, ume is the mass of the planet 5.1e24 kg
m is the mass of the space ship 5.9e4 kg
( g) o1 X, g; y  k5 J" 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

6 X9 @1 H% [" g8 A用这个公式错了么?
还是说只是纯粹的计算出错?

chulinlong

3# Maths
& C- D8 S- Y" |" _& t( k
# L( q4 _) d. m+ M* \
; K* z+ P3 |6 o: V: [. _' N4 z这个公式对的