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प्रश्न
1 H.P. is equal to
विकल्प
1 W
1 J
746 J
746 W
उत्तर
746 W
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संबंधित प्रश्न
A body is moving unidirectionally under the influence of a source of constant power. Its displacement in time t is proportional to ______.
The blades of a windmill sweep out a circle of area A.
- If the wind flows at a velocity v perpendicular to the circle, what is the mass of the air passing through it in time t?
- What is the kinetic energy of the air?
- Assume that the windmill converts 25% of the wind’s energy into electrical energy, and that A = 30 m2, v = 36 km/h and the density of air is 1.2 kg m–3. What is the electrical power produced?
Match the following
| column A | Column B |
| A stone at a height | power |
| A Moving ball | joule |
| Energy | work done in 1 s |
| Power | potential energy |
| Watt | kinetic energy |
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Name the physical quantity which is measured in calorie. How is it related to the S.I. unit of the quality?
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- kWh,
- joule.
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An engine pumps up 200 kg of water through a height of 20 m in 10 seconds. If the efficiency of the engine is 80%. Calculate the power of the engine.
Calculate the power of a crane in watts, which lifts a mass of 100 kg to a height of 10 m in 20s.
Name the quantity which is measured in Wh.
