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प्रश्न
When does a force perform work?
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उत्तर १
Work is said to be done only when the force applied on a body makes the body move (i.e. if there is some displacement or motion occurred due that force).
उत्तर २
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Displacement Occurs: The object on which the force is applied must move (displace) in response to the force.
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Component of Force Along Displacement: There must be a component of the applied force in the direction of the displacement.
Formula for Work:
Work = Force × Displacement × cos θ
θ is the angle between the force and displacement directions.
Key Points:
- If the displacement is zero, no work is done, even if a force is applied.
- If the force is perpendicular to the displacement (θ = 90°), no work is done because cos 90°.
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