Same chapter2 marksDifficulty: Easy
A force of 35 N moves a body through 6 m in the direction of the force. Calculate the work done.
Work, Energy and Power
2 marksDifficulty: Easy
When is the work done by a force zero, even though the force acts on a moving body?
Original Khojo Papers practice question — not from a past board paper.
Answer
The work is zero when the displacement is perpendicular to the force, because work is F × s × cos θ and cos 90° = 0. This is why no work is done by the centripetal force on a body moving in a circle, and none by gravity on a body carried horizontally.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Work is also zero when there is no displacement at all.
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