Concept explainers
It is often said that astronauts in orbit experience weightlessness because they are beyond the pull of Earth’s gravity. Is this statement correct? Explain.
Answer to Problem 1CQ
Explanation of Solution
The astronaut in the orbit around the earth is under two forces that are gravitational force and centrifugal force. The gravitational force acts on the astronaut is due to the earth’s gravitational pull.
Due to the tangential velocity of the astronaut in orbit, the acceleration is in direction away from the earth. The centrifugal force due to this acceleration is also in direction away from the earth. Thus the astronaut in the orbit feels weightless because the centripetal force applied on the astronauts by earth’s gravitational force is balanced by the centrifugal force due to orbital velocity of the satellite.
Conclusion:
Therefore, the force due to earth gravitational pull on an object is zero at infinite distance, the net force on the astronauts is zero.
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