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प्रश्न
State the S.I. units of electrical power and electrical energy.
(i) Define the household unit of electricity.
(ii) What is the voltage of the electricity that is generally supplied to a house?
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उत्तर
The SI unit of electrical energy is joule.
The SI unit of electrical power is watt.
(i) Kilowatt-hour is the household unit of electrical energy. It is defined as the quantity of electrical energy consumed in 1 hour when the rate of consumption is 1000 watts, i.e. 1000 J/s.
(ii) A voltage of 220 volt is generally supplied to a house.
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संबंधित प्रश्न
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(iv) Name one device which works on this principle.
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What is ‘Rating’ of an electric appliance?
A house is provided with 15 bulbs of 40W, 5 bulbs of 100W, 5 fans of 80 W, and one heater of 1.0 kW. Each day bulbs are used for 4h, fans for lOh, and heater for 2h. The voltage of mains is 220 V. Calculate:
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(ii) maximum current capacity of the main fuse in the house,
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