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प्रश्न
State two conditions when no work is done by a force.
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उत्तर
Two conditions are:
- No work is said to be done if there is no change in position or no motion even after the application of force. There should be no displacement i.e. S = 0
- When the angle between the displacement and force applied is 90 degrees i.e the force applied is perpendicular to the displacement. The displacement is NORMAL to the direction of FORCE i.e. –θ = 90°
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