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प्रश्न
State (i) the S. I. unit, (ii) the household unit, of electrical energy. How are these units related?
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उत्तर
(i) The S.I. unit of electrical energy is joule (J)
(ii) The household unit of electrical energy is kilo-watt hour (kWh).
Relationship: 1 kWh = 1 kW × 1h
= 1000W × 3600 s
= 3.6 × 106 J.
संबंधित प्रश्न
What is meant by "electric power"?
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Write the SI units for:
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Find the energy released by a current of 0.25 amperes flowing through a heater for 5 minutes. The p.d. is 230 V.
A bulb is connected to a battery of e.m.f. 6V and internal resistance 2Ω A steady current of 0.5A flows through the bulb. Calculate the total energy supplied by the battery in 10 minutes.
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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