# circular motionWatch

#1
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...
0
9 months ago
#2
Na you no unknowns cuz the M and G cancels and you're left with the r squared.
1
#3
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
0
9 months ago
#4
(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.

1
#5

I forgot I had to form a proportionality equation, thank you both
0
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