circular motion Watch

znx
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A satellite is in a circular orbit around the earth. The vertical height of the satellite above the surface of the earth is 3200km. The radius of the earth is 6400km.

What is the ratio: weight of satellite in orbit/weight of satellite on the earths surface?

A) 0.25
B) 0.44
C) 0.5
D) 0.67

I dont really know how to do this question, I thought of using g = GM/r^2 for the satellite in orbit, but I have two unknowns...
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Radioactivedecay
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Na you no unknowns cuz the M and G cancels and you're left with the r squared.
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znx
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(Original post by Radioactivedecay)
Na you no unknowns cuz the M and G cancels and you're left with the r squared.
but how would I find the weight of the satellite since they haven't given the mass of the satellite
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Eimmanuel
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(Original post by znx)
but how would I find the weight of the satellite since they haven't given the mass of the satellite
All the "unknown" will be cancelled when you place them into a fraction of a fraction.

 \dfrac{\frac{GMm}{r_1^2}}{\frac{  GMm}{r_2^2}}
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znx
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@Radioactivedecay @Eimmanuel

I forgot I had to form a proportionality equation, thank you both
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