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प्रश्न
A coolie, with a load of 30 kg on his head, walks on the platform. If he walks a distance of 60 m, what is the work done by him?
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उत्तर
The work done by the coolie is zero because there is no displacement of’ the load in the direction of force, which he is applying vertically upwards.
संबंधित प्रश्न
The S.I. unit of energy is .............
A boy of weight 40 kgf climbs up the 15 steps, each 15 cm high in 10 s and a girl of weight 20 kgf does the same in 5 s. Compare:
- the work done, and
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A box of weight 150 kgf has gravitational potential energy stored in it equal to 14700 J. Find the height of the box above the ground. (Take g = 9.8 N kg-1)
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Is work a scalar or a vector quantity?
Write the formula for work done on a body when the body moves at an angle to the direction of force. Give the meaning of each symbol used.
Can two agents, doing the same work, have different power?
