For certain space-based experiments a satellite must provide its occupants with an effective downward acceleration of only 3.0ms−2 while they remain in a circular orbit around the Earth.
a. (a) Calculate the orbital radius (measured from the Earth’s centre) at which the centripetal acceleration of the satellite equals 3.0ms−2. Use ME=5.97×1024kg and G=6.67×10−11Nm2/kg2.
b. (b) Hence find the altitude of this orbit above the Earth’s surface (RE=6.37×106m).
c. (c) For an astronaut of mass 70kg inside the satellite, calculate the gravitational force acting on the astronaut at that altitude and express it as a percentage of the astronaut’s weight at the Earth’s surface.