(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A satellite in a circular orbit around Earth has a speed of 7.15x10^{3}m/s. Determine, in terms of Earth's radius (radius of earth= 6.38 x10^{6}m):

a) the distance the satellite is from Earth's centre

b) the altitiude of the satellite

2. Relevant equations

F_{G}= GMm / r^{2}

F_{c}= mv^{2}/ r

G = 6.67 x 10^{-11}

3. The attempt at a solution

I'm seriously unsure on how to even start on this one, because I'm not sure what they mean by 'in terms of Earth's radius.' The answer key says 1.22 r_{earth}for a. Do you have to do this through proportionality and ratios?

In terms of writing down the given/known:

v = 7.15 x 10^{3}m/s

r_{earth}= 6.38 x 10^{6}m

M_{earth}= 5.98 x 10^{24}kg

G = 6.67 x 10^{-11}Nm^{2}/kg^{2}

I can't figure out the force of gravity because I don't have the mass of the satellite, so that cancels out finding F_{c}as well since I need the mass for that too.

Any help on how to start this would be appreciated, thank you.

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# Homework Help: Distance from Satellite to Earth Question

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