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Satellites (1 Viewer)

TeaYarn

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Two satellites, X and Y, orbit the earth. The mass of satellite X is twice that of satellite Y. The orbital radius of satellite Y is twice that of satellite X.
What is the ratio of the orbital speed of satellite X to the orbital speed of satellite Y?
A) 1:1
B) 1:√2
C) √2:1
D) 2:1

Please show all working
 

cub3root

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I am going to guess B) because if the satellite is further away it will need to be faster in order to "catch up"
 

anomalousdecay

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I am going to guess B) because if the satellite is further away it will need to be faster in order to "catch up"
I think its the wrong order lel. Orbital speed is different. Use the formulas.



M is the mass of the Earth, r is the radius of orbit and G is the universal gravitational constant.

So the mass of the satellite's don't affect the required orbital velocity.

Satellite Y has twice the orbital radius. So then the required orbital velocity of satellite Y is less by a factor of 1/sqrt(2).

Hence X:Y is 1: 1/sqrt(2)

Hence X:Y is:

 

cub3root

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oops it says X:Y

yeah should be other way around
 

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