(adsbygoogle = window.adsbygoogle || []).push({}); A typical GPS (Global Positioning System) satellite orbits at an altitude of 2.0e7 m.

Find the orbital speed of such a satellite in km/s.

So we know:

Mass of the earth (M) =5.97e24

Radius of the earth (R) =6.37e6

G is constant =6.67e-11

I used the equation:

Final velocity=square root (2GM/R)

square root ((2*6.67e-11*5.97e24)/(6.37e6+2.0e7))

And dividing the answer by 1000 to obtain km/s I get 5.50km/s.

The answer is 3.9km/s.... I think my error may be related to adding the altitude to the radius of the earth at the bottom of the equation, but I'm not sure.

Thanks guys!

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# Homework Help: Speed of satellite

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