Time period of satellite moving around a planet with angular velocity
ω is given as,
T= Since, the two artificial satellites revolving in the same circular orbit, then their angular velocities will be same.
Hence, both satellites revolve with same period of revolution.
Orbital velocity of revolving satellite,
v=√i.e
v∝ Where,
m= mass of the planet
G= Universal gravitational constant
r= radius of circular orbit.
Escape velocity depends on the gravitational potential at the point from where the body is launched. Since, this potential depends on the height of the point of projection, hence escape velocity also depends on the height (altitude) of the point of projection.