What is meant by power of a machine ? Name and define its SI unit. How is kilowatt different from kilowatt hour ? From a 20 m high fall nearly 25 metric tonnes of water fall per second. Calculate the equivalent power if all its energy is utilized. ( g = 10 m/s)
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Power means rate of work done. P = w/t
Unit of power = unit of work/ unit of time = j/s = js raise to power –1 = watt or simply W
1kW is thousand times of 1W. 1kW = 1000W
1kW h is the bigger unit for work used mostly for machines. 1kW h = 3.6 * 10 raise to power 6 J
In the Ques, height = 20m, mass = 25 metric tonne = 25000 Kg, Acceleration = 10ms raise to power –2
Work = mgh = 25000*10*20 = 50,00,000 J = 5000 Kj
Power can't be found due to nothing given about time taken.
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power of a Machine is a the extent of work that can be done with the help of machine in a particular time period.,which save the energy and helps in performing the task with ease.
power means the rate of work done = P = W/t
SI unit = watt
1 kilo watt = 1000 watt
1 kW hr is the bigger unit usually used for machines so, 1 kW hr = 3.6 x 10⁶J
work = mgh = 25000 x 10 x 20
= 50,00000J = 5000 Kj
power means the rate of work done = P = W/t
SI unit = watt
1 kilo watt = 1000 watt
1 kW hr is the bigger unit usually used for machines so, 1 kW hr = 3.6 x 10⁶J
work = mgh = 25000 x 10 x 20
= 50,00000J = 5000 Kj
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