The motion of low orbit satellites can be approximated by saving that the needed centripetal acceleration for the circular orbit is equal to g= 9.8m/sec2 (the gravitational acceleration as observed on the surface of Earth). Using this assumption and neglecting any problem due to the atmosphere.
What is the orbital speed of the satellite?
Setting the radius of the orbit equal to the radius of the Earth Rt= 6400km. How long does it take for one orbit?
What is the weight of the astronauts on board of the satellite? Explain why?