An astronaut experiences weightlessness in a space satellite. It is because

Options

A. no external force is acting on him
B. he is falling freely
C. no reaction is exerted by the floor of the satellite
D. he is far away from the earth's surface

Answer

B, C

Explanation

For an earth satellite moving in a circular orbit, the centripetal force required for its circular motion is provided by the gravitational force exerted by the earth on it.
It means the resultant force on the astronaut is equal to the gravitational force exerted by the earth on him. Hence, no reaction is exerted by the floor of the satellite on him.
In oter words his acceleration towards the earth's centre (centripetal acceleration) is exactly equal to acceleration caused by the gravitational force.
Hence, option b and c are correct.