A satellites period, the time it takes it to go around the earth, is determined, in part, by its altitude.
The further away it is then the longer it will take.
You can calculate an altitude where it will take just one day to make an orbit. If this is done then though the satellite orbits the earth it appears to be stationary above one point of the earth. This orbit must be above, or very near to, the equator. For the earth this altitude is approximately 36,000 km (22,000 miles)
Geostationary satellite
Aryabhatta
A geostationary satellite does not trace a path over the surface of the earth because that is what geostationary means - the satellite is stationary over a point on the Earth.
A geostationary orbit will keep the satellite in one area relative to the surface
Geostationary satellites are in an orbit that's 22,282 mi (35,786 km) above the surface of the Earth. For more on Geostationary satellite orbits, visit http://www.idirect.net/Company/Satellite-Basics/How-Satellite-Works.aspx
they fly in air
A geostationary satellite appears to stand still to a viewer anywhere on the earth, not just on the equator.
No. A geostationary satellite appears to be stationary in the sky, which means not moving. This is a big part of the reason why it is referred to as a geo'stationary' satellite.
It should be possible to have the perfectly geostationary satellites. But it is not possible. Perfectly geostationary satellite can not be made. Such satellite is pulled away by other objects like moon, sun and other planets from different directions. This force changes the velocity of the satellites.
its location
Aryabhata in 1975
24 hours