If a 2000kg satellite orbits around the earth at the height of 300km, what is the speed of the satellite and its period?


The orbital speed is independent of the mass of the satellite if the mass is much less than that of the Earth so.

The equation for orbital velocity is v = Square Root (GM / r)

Where v is the linear velocity

G is the gravitational constant = 6.674×10^-11 m^3kg^-1s^-2

M is the mass of the Earth = 5.9722 × 10^24 kg

and r is the distance from the Earth to the satellite = 300 x 10^6 metres

Also v = rw = but w = 2PI/T

where w is the angular velocity

and T is the period of orbit,

So substituting gives

v = r(2PI/T)

And rearranging

T = r2PI/T or T = 2PIr/v

substitute the values r = 300 x 10^6 and v calculated previously to get T

Updated on March 16, 2018

Original Article:

Force, Mass, Acceleration and How to Understand Newton's Laws of Motion
By Eugene Brennan