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प्रश्न
A max X goes to the top of a building by a vertical spiral staircase. Another man Y of the same mass goes to the top of the same building by a slanting ladder. Which of the two does more work against gravity and why?
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उत्तर
'X’ and ‘Y’ are two persons doing the same amount of work against gravity in climbing to the top of the building. Work done against gravity depends on the vertical distance through which the body is lifted and is independent of the path travelled to achieve that height. Both men travel the same distance vertically, so the work done by them against gravity is equal.
संबंधित प्रश्न
Define the term energy.
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(i) A man pushing a wall.
(ii) a coolie standing with a load of 12 kgf on his head.
(iii) A boy climbing up a staircase.
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The loss in potential energy of the body,
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State the law of conservation of energy.
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Choose one or more correct alternatives.
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- transferred from one place to another
- concentrated
- transformed from one type to another
- destroyed
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Joule is the unit of .......
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Look at the activity below. Reason out whether or not work is done in the light of your understanding of the term ‘work’.
An engine is pulling a train.
