Question

a satellite revolves around the earth along a circular path if the mass of the satellite is 1000 kg and its distance from the centre of the Earth is 20000 kilometre find the magnitude of the earth gravitational force acting on the satellite​

Answer 1

Let, a satellite of mass m goes around the earth in a circular orbit of radius r=R+R=2R. Here the centripetal force mv

2

/r necessary to keep the satellite in its circular orbit is provided by the gravitational force GMm/r

2

between the earth and the satellite.

Thus, mv

2

/r=GMm/r

2

or v=

r

GM

=

2R

GM

Acceleration at the earth's surface is g=

R

2

GM

So, v=

2R

gR

2

=

gR/2