An astronaut whose weight on the Earth is 600 N experiences weightlessness on International Space Station orbiting around the Earth. It means that
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This question was previously asked in
UPSC NDA-2 – 2024
– The ISS and everything in it, including the astronaut, are constantly in freefall around the Earth. They are orbiting because they have a high tangential velocity while simultaneously accelerating towards the Earth due to gravity.
– In freefall, there is no supporting surface providing a normal reaction force to counteract gravity. The feeling of weight comes from this reaction force. Since this support force is absent, the astronaut feels weightless.
– The gravitational pull of Earth on the astronaut is not zero in orbit; it is still significant (around 90% of Earth’s surface gravity at ISS altitude) and is what keeps the ISS in orbit.
– The astronaut is accelerating towards the Earth (centripetal acceleration required for circular motion), so their acceleration is not zero.
– Centrifugal force is a fictitious force experienced in a rotating frame of reference; it’s not a real force causing weightlessness.