When a rocket is launched, it starts not with velocity zero, but with the rotation velocity which the Earth gives it. Thus if a rocket is launched eastward, it requires a smaller boost (and if westward, a larger one) to achieve orbit. with a latitude of 31.1 degrees, cos(31degrees) 24902/24 = 393.11 ms/s(adsbygoogle = window.adsbygoogle || []).push({});

To escape velocity on earth = (2G Mearth / r earth) = 11200ms-1

So the total velocity that needed for the rocket = 11200 - 393.11= 10806.99ms-1

I am trying to find the total energy that is needed for the rocket of 1000kg to escape velocity

i used the question

m = 1000 x 9.8 N

E= 1/2 m^2

= 5.84 X 10^10 J

my question is : as the further you are away from earth, there will be less gravity. So if i use that equation, would that be accurate assume there is no air friction and the mass of the rocket doesnt change due to the loss of fuel

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# Homework Help: The rocket launch and changing gravity

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