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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]
1 h) a6 i2 B; d1 c) R. _1 E
! m+ A2 m5 _) n R8 Z[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]
& |1 a2 B2 `" P& @2 D7 I) R
' C8 g/ k7 y/ X; ^) }
' H( m. F+ v8 D7 z! o6 c. N# @so far what I have done is used the equation for GPE
% _" Y: h' S9 n: X5 q( ^4 P) a. k# mwhich is ! ~, j) V6 I: m' Y. n: C4 ~
U = - (G me m) / r2 R0 d) k0 @; X) F7 S! F1 x3 P' {
+ l9 P9 |$ G1 [" R/ r2 u
where G is 6.674e-11 Nmkg-2, u2 h9 N9 s% t3 p, B) G
me is the mass of the planet 5.1e24 kg
, B* j$ o9 ]8 T$ [m is the mass of the space ship 5.9e4 kg
7 ^5 @( b. o" |, r5 jr 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 |
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