A satellite is to
be placed in an free  flight equatorial circular orbit around earth.
The satellite remains stationary with respect to a point on earth. Determine
the radius of the circular orbit. a ) 4.22 ( 10^{
4} ) Km 

Let R be the radius of the circular orbit ; M _{e }, the mass of the earth ; M _{s} the mass of the satellite ; w , be the angular velocity of the satellite and G be the universal gravitational constant. Since the satellite is in the free  flight equatorial circular orbit the net normal force on the satellite should be zero. Given that the satellite remains stationary with respect to a point on the earth , its time  period must be 24 hours = 86400 s. hence the angular acceleration of the satellite is given by , w = ( 2 p ) / 86400 = 7.272 ( 10 ^{  5} ) Writing the equation
of motion in the radial direction , The radius of the orbit is 4.22 ( 10^{ 4} ) Km 