 鲜花( 0)  鸡蛋( 0)
|
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]( G" R: p0 K# o
1 K# X+ U+ _# s% w1 E[Specify units of 'J', 'kJ', 'MJ' or 'GJ' in your answer.]; {0 U& Q* v P, L+ O4 n- l
/ x* V# {: M, ^0 ^
& G/ p: s) h3 b* O/ r. K2 W5 I/ j
so far what I have done is used the equation for GPE/ y1 t0 o8 r8 [9 g0 O% g6 \0 m/ N
which is , ?2 T7 |* h7 k- v
U = - (G me m) / r
1 Z, y+ j0 k0 @$ X" O1 d
+ B" g9 I t2 F8 h) L, twhere G is 6.674e-11 Nmkg-2: j; D) c, R* P- b( g
me is the mass of the planet 5.1e24 kg % s D( [. [) G
m is the mass of the space ship 5.9e4 kg 8 n: A! w( d" e9 M! y: E$ C7 l f
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 |
|
狗仔卡
发表于 2009-11-10 21:41
提升卡
置顶卡
沉默卡
喧嚣卡
变色卡
显身卡
楼主
