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प्रश्न
What is the commercial unit of electrical energy? Represent it in terms of joules.
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उत्तर
The commercial unit of electrical energy is Kilowatt hour (kWh)
1 kWh = 1000 W × 1 h
`1 "kWh" = 1000 "J"/"s" × 3600 "s"`
1 kWh = 3.6 × 106 J
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संबंधित प्रश्न
State two factors on which the electrical energy consumed by an electrical appliance depends.
The unit for expressing electric power is:
(a) volt
(b) joule
(c) coulomb
(d) watt
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State and define the household unit of electricity.
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Why is a concave reflector placed behind the heating element in a room heater.
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State two advantages of filling an inert gas in an evacuated electric filament lamp.
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State the reason why, in a three pin plug, the earth pin is longer and thicker than the other two.
A battery of e.m.f. 12V and internal resistance 1.6 Ω is connected to two resistors of 4Ω and 6Ω connected in parallel. Calculate:
(i) the current drawn from the battery,
(ii) the power dissipated in each resistor,
(ii)the total power supplied by the battery.
