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(a) Define power. Give the SI unit of po...

(a) Define power. Give the SI unit of power.
A boy weighing 40 kg carries a box weighing 20 kg to the top of a building 15 m high in 25 seconds. Calculate the power. (`g = 10 m//s^(2)`)

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The correct Answer is:
(b) 360 W
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LAKHMIR SINGH & MANJIT KAUR-WORK AND ENERGY-Exercise
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  2. (a) Derive the relation between commercial unit of energy (kWh) and SI...

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  3. (a) Define power. Give the SI unit of power. A boy weighing 40 kg ca...

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  4. When a body falls freely towards the earth, then its total energy

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  5. Which one of the following is not the unit of energy?

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  6. Which of the following energy change involves frictional force?

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  7. An electric motor raises a load of 0.2 kg, at a constant speed, throug...

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  8. An object is falling freely from a height x. After it has fallen a hei...

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  9. COMMERCIAL UNIT OF ENERGY

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  10. How much energy does a 100W electric bulb transfer in 1 minute?

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  11. The device which converts mechanical energy into energy which runs our...

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  12. A microphone converts

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  13. The following data was obtained for a body of mass 1 kg dropped from a...

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  14. A ball falls to the ground as shown below : (a) What is the kinet...

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  15. In an experiment to measure his power, a student records the time take...

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  16. In loading a truck, a man lifts boxes of 100 N each through a height o...

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  17. Name the energy transfers which occur when : (a) an electric bell ri...

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  18. A force of 7 N acts on an object. The displacement is, say 8 m, in the...

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  19. When do we say that work is done ?

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  20. Write an expression for the work done when a force is acting on an obj...

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