The uniform circular motion centripetal force equation can be calculated a first speed of the universe, the same token, the satellite can be calculated revolution speed v at the track radius r.
Satellites orbiting the Earth to be seen as a uniform circular motion, so that, provided the earth mass is M, the satellite mass is m, the track radius r, the Earth and the satellite particle considered, r is the distance to the satellite geocentric.
Gravity of the satellite F primer = GM m / r²
Satellite revolving uniform circular motion to the centripetal force F = m v² / r
Because the F primer = F,
Therefore, GM m / r² = m v² / r,