# Orbital Velocity of Satellite

Orbital velocity of a satellite is the velocity required to put the satellite into its orbit around the Earth.

[as GM = gR2 and r = R + h]

Important Points
• Orbital velocity is independent of the mass of the orbiting body and is always along the tangent of the orbit, i.e., satellites of deferent masses have same orbital velocity, if they are in the same orbit.
• Orbital velocity depends on the mass of central body and radius of orbit.
• For a given planet, greater the radius of orbit, lesser will be the orbital velocity of the satellite .
• Orbital velocity of satellite when it revolves very close to the surface of the planet,

[As h = 0 and GM = gR2]

For Earth,

= 7.9 km/s â‰ˆ 8 km/s
• Close to the surface of planet,

âˆ´ , i.e.,

It means that if the speed of a satellite orbiting close to the Earth is made  times (or increased by 41%), then it will escape from the gravitational field.