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प्रश्न
Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
A wind-mill is lifting water from a well.
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उत्तर
- A wind-mill works against the gravitational force to lift water.
- Hence, work is done by the wind-mill in lifting water from the well.
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संबंधित प्रश्न
Define the term energy.
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Choose one or more correct alternatives.
Joule is the unit of ______.
- force
- work
- power
- energy
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(i) P.E. maximum,
(ii) K.E. maximum,
(iii) P.E. = K.E.?
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(i) Gravitational force acting on the girl.
(ii) Work done by her.
(iii) Useful work done by her.
(iv) Her power in watt.
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