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]
9 L7 a5 a" A- \& L
* Z- `! C( S) K, D* g" P; R' P, ~& f[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]
, ~; n* }4 c  x0 q

$ {! R2 V' w* z4 n8 Yso far what I have done is used the equation for GPE
which is
U = - (G me m) / r

! ~6 T4 l$ }. H5 [5 S9 P/ vwhere G is 6.674e-11 Nmkg-2
3 b! o, g" c3 s% zme is the mass of the planet 5.1e24 kg
. s7 T( p) T; ^; Fm is the mass of the space ship 5.9e4 kg
) I) X" D4 ]! W- Y; Kr 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?
) d1 @5 J3 _) Q* }/ d# A0 y( U还是说只是纯粹的计算出错?

chulinlong

3# Maths
! P& \+ @9 u8 t% q
; `' k! h2 u' }
# U8 w4 {1 G  B+ P这个公式对的