Speed of satellite in circular orbit

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thatgirlyouknow
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Homework Statement



A satellite is in a circular orbit about the Earth (M = 5.98 x 1024 kg). The period of the satellite is 9.93 x 104 s. What is the speed at which the satellite travels?

Homework Equations



v=(2*pi*r)/T

v=sqrt((GMe)/r)

The Attempt at a Solution



sqrt[((6.67x10^-11)*(5.98x10^24))/r) = 2*pi*r / T
T = 2piR^3/2 / (sqrt[GMe])
r = 8.414 x 10^15
v = 2*pi*r / t
v = 5.324 x 10^11 m/s
 
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thatgirlyouknow said:

Homework Statement



A satellite is in a circular orbit about the Earth (M = 5.98 x 1024 kg). The period of the satellite is 9.93 x 104 s. What is the speed at which the satellite travels?

Homework Equations



v=(2*pi*r)/T

v=sqrt((GMe)/r)

The Attempt at a Solution



sqrt[((6.67x10^-11)*(5.98x10^24))/r) = 2*pi*r / T
T = 2piR^3/2 / (sqrt[GMe])
r = 8.414 x 10^15

your formula looks right but I think r is wrong... check your calculations
 
Ok after reworking I got that r = 46357704 m. So:

v = sqrt[(GMe)/r]
v = sqrt[(6.67x10^-11*5.98x10^24)/(46357704)]
v = 3594.51 m/s

But this still isn't right. Are my calculations wrong at some point?
 
Ok I worked it again and got v = 2933.27 m/s. (Hooray human error). Can anyone verify that as correct?
 
thatgirlyouknow said:
Ok I worked it again and got v = 2933.27 m/s. (Hooray human error). Can anyone verify that as correct?

yes, looks right to me.