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]
+ H9 H. k$ p, ~: D# j
: e' F7 |  c1 L9 J% Z[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]

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8 E" o% c4 z0 u0 i2 @7 f3 bso far what I have done is used the equation for GPE
which is
U = - (G me m) / r
' f7 c/ b: a; t" o+ l7 C
where G is 6.674e-11 Nmkg-2
me is the mass of the planet 5.1e24 kg
7 \2 u. r# ^( @9 em 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

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用这个公式错了么?
/ G. ^4 O- v' n/ F. r还是说只是纯粹的计算出错?

chulinlong

3# Maths
7 t5 N' T" o. q  }! x7 Q% _
, F# l; L& W2 f6 x( ^+ A1 r" `  _
2 t; i) `& L" ]& v( y9 J/ {; ]+ z8 L; R6 G这个公式对的