A satellite moves in a circular orbit around the Earth at a constant speed. The work done by the gravitational force on the satellite is: MCQ with Answer and Explanation

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A satellite moves in a circular orbit around the Earth at a constant speed. The work done by the gravitational force on the satellite is:

A. Zero

B. Maximum

C. Positive

D. Negative

Answer: Option A

Solution (By JKExamLibrary)

Work is defined as W = F.d.cos(θ). For a satellite in a circular orbit, the gravitational force acts as the centripetal force, directing entirely towards the center of the Earth. The displacement of the satellite at any instant is tangential. Since the angle between force and displacement is exactly 90°, cos(90°) = 0, meaning zero work is done.

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A. t

B. t/2

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Correct Answer: Option D

Explanation:
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Correct Answer: Option C

Explanation:
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This question belongs to: Science Physics