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प्रश्न
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उत्तर
Examples of potential energy:
(i) Water stored at a height in a reservoir.
(ii) A stretched spring.
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संबंधित प्रश्न
A coolie does no work against the force of gravity while carrying a luggage on a road.
In which of the following cases, is work being done?
(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.
1 J = ______ calorie.
.A man raises a box of mass 50kg to a height of 2m in 20s, while another man raises the same box to the same height in 50s. Compare:
(i) the work done, and
(ii) the power developed by them.
Give one example each in which a force does (a) positive work (b) negative work, and (c) zero work.
In case of negative work, the angle between the force and displacement is :
A uniform circular motion is an accelerated motion. Justify it.
A machine raises a load of 750 N through a height of 16 m in 5s. calculate:
(i) work done by machine,
(ii) power at which the machine works.
A girl of mass 50 kg runs up a flight of 40 steps in 20 seconds. If each step in 20 cm high, calculate the power developed by the girl. (g= 10 ms-2).
