Orbital Velocity

Orbital Velocity is the velocity which is give to an artificial earth's satellite a few hundred kilometers above the earth's surface so that it may start revolving round the earth. It is denoted by V_o.

Expression for orbital velocity

Let, m = Mass of satellite

r = radius of circular orbit of satellite

h = height of satellite above surface of earth.

R = radius of earth

V_o = orbital velocity

M = Mass of the earth.

The

required by the satellite to keep moving in a circular orbit is produced by the gravitational force

between the satellite and the earth. Therefore,

Here r=R+h

Let gh be the acceleration due to gravity at heigh h

Therefore, weight of satellite = Mgh

Force of attraction between body (Satellite) and earth must be balance by weight of satellite.

or

substituting above value of GM is eg.(2)

we get, orbital velocity

Remember, rockets are used to move the body to required height and we can place space shuttle or satellites in earth's orbit.