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Question
How much work is done by the gravitational force of earth acting on a satellite moving around it in a circular path? Give reason for your answer.
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Solution
The relation between work, force, distance and angle between the two is:
W = (F) (S) cos θ
Where,
(W) - Work done
(F)- Force
(S)- Displacement
(θ) - Angle between force and displacement
The work done by the earth on a satellite moving in a circular orbit around it is zero, as gravitational force is perpendicular to the direction of motion at every instant, and hence, the work done is zero.
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