capa8 - 1) Energy = Power * Time Units: 1 Joule = 1 Watt *...

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1) Energy = Power * Time Units: 1 Joule = 1 Watt * 1 second (One day has 24*60*60 s = 86400 seconds) 2) M 3 would ‘experience’ no net-gravitational force if F grav 31 = F grav 32 . According to Newton’s universal law of gravity we can express the gravitational forces in terms of the masses of the three objects and we find: G·M 1 ·M 3 / x 2 = G·M 2 ·M 3 / y 2 b x 2 /y 2 = M 1 /M 2 (M 3 and G cancel on both sides) With y = d 12 – x we can write x = sqrt(M 1 /M 2 )·(d 12 – x) , (‘sqrt’ = ‘square root’) or: x = c·d / (1+c) , with c = sqrt(M 1 /M 2 ). 3) F grav = mg 4) F grav by sun / F grav by moon = [G·M sun · m / R 2 sun-earth ] / [G·M moon · m / R 2 moon-earth ] = M sun · R 2 moon-earth / (M moon · R 2 sun-earth ) 5) The escape velocity is the speed at which the kinetic energy is eqal to the gravitational potential energy U g = - G M·m / R, where M and m are the masses of the planet and the projectile, respectively. R is the radius of the planet if the projectile is launched from the
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capa8 - 1) Energy = Power * Time Units: 1 Joule = 1 Watt *...

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