Answer to Question #121142 in Classical Mechanics for Lizwi

Question

The reason an astronaut in an earth satellite feels weightless is that
1 : the astronaut is beyond the range of the earth's gravity.
2 : the astronaut is falling.
3 : the astronaut is at a point in space where the effects of the moon's gravity and the earth's gravity cancel.
4 : this is a psychological effect associated with rapid motion.
5 : the astronaut's acceleration is zero

Answer 1

In an earth satellite, each object feels weightless because they are in a free-fall condition towards the earth. The satellite and the astronauts, both are in a state of freefall. Option B is correct. The astronaut's acceleration is falling.

The satellite with the astronaut moves in the orbit with very high speed and they tend to fall towards the earth. Since satellites and astronauts are falling with the same acceleration so the normal force or the weight felt by the astronaut is zero.