A geostationary satellite is orbiting Earth, a) What is meant by a geostationary orbit? b) Calculate the height at which the satellite orbits above the surface of the Earth. The radius of the Earth is 6400km and its mass is 6x10^24 kg.

a) A geostationary orbit is when the satellite remains vertically above the same point on the equator at all all times and consequently has an orbital period of 24 hours. b) Use the equation T^2=4(PI)^2(r)^3/GM and rearrange for r. You can then just substitute the values into the equation to find the answer for r. It is important to subtract 6400km at the end because the question asked for the distance from the surface not the centre of the Earth. The final answer is r=3.6x10^7m.