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MiniTank
May25-05, 10:24 PM
I am having some difficulty with this question:
A satellite is in orbit around Earth at an altitude of 3700 km. How much must its speed increase, in km/h, to escape the Earth's force of gravity?

I'm stumped. Please help

whozum
May25-05, 10:27 PM
Whats Earth's escape velocity?
What velocity is it orbitting at if its at that altitude?

MiniTank
May25-05, 10:33 PM
Earth's escape velocity = 1.12 x 10^4 m/s
and the velocity at that altitude is what im having tourble with

whozum
May25-05, 10:34 PM
Find the gravitational potential energy at that altitude. What doy ou know about the satelite's KE if it remains at that point?

MiniTank
May25-05, 10:42 PM
i think i get what your saying ..

Ek = 1/2 |Eg|
\frac{1}{2}mv^2 = \frac{1}{2}\frac{GMm}{r}
v=\sqrt{\frac{GM}{r}}

after i find that .. do i subtract that velocity from the escape velocity of earth?

whozum
May25-05, 10:46 PM
Fix your tex tags, slash them the other way, /tex

whozum
May25-05, 10:55 PM
You've got all youj need to solve the problem.

MiniTank
May25-05, 10:58 PM
alright thanks ... appreciate it