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प्रश्न
What is the condition for a force to do work on a body?
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उत्तर
The necessary condition for force to do work is that the applied force should produce motion in the body in any direction except the direction perpendicular to the force applied.
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संबंधित प्रश्न
A coolie is moving on a road with a luggage on his head. Does he perform work against the force of gravity? Give reason for your answer.
A boy of mass 40 kg climbs up the stairs and reaches the roof at a height 8 m in 5 s. Calculate:
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- the work done by him against the force of gravity,
- the power spent by boy. (Take g = 10 m s-2)
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- the power developed by him. Take g = 10 N kg-1
State the SI unit of work.
Give one example in which a force does zero work.
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