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Question
A person sitting in a chair in a satellite feels weightless because
Options
the earth does not attract the objects in a satellite
the normal force by the chair on the person balances the earth's attraction
the normal force is zero
the person in satellite is not accelerated.
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Solution
the normal force is zero
The gravitational pull on the satellite is used up in providing the necessary centripetal force required for its revolution around the earth. This means that there is no net force on the person sitting in a chair in the satellite. So, the normal reaction of the chair on the person is zero and he will feel weightless.
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