An astronaut of mass 75kg is orbiting Earth in an artificial satellite that is in a state of continuous free fall around the planet.
(i) What is the numerical value of the astronaut’s mass while he is in orbit? Give reason.
(ii) Explain why the astronaut experiences a sensation of weightlessness even though Earth’s gravitational pull is still acting on him.
(iii) Distinguish between actual weight and apparent weight in this situation. Which of the two is zero for the astronaut?
(iv) State whether mass and weight are scalar or vector quantities, justifying your answer briefly.