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प्रश्न
The ‘live’ and the ‘neutral’ wires have potential difference of _______.
पर्याय
110 V
202 V
201 V
220 V
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उत्तर
The ‘live’ and the ‘neutral’ wires have potential difference of 220 V.
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संबंधित प्रश्न
Why does the cord of an electric heater not glow while the heating element does?
An electric heater of resistance 8 Ω draws 15 A from the service mains 2 hours. Calculate the rate at which heat is developed in the heater.
Why are the conductors of electric heating devices, such as bread-toasters and electric irons, made of an alloy rather than a pure metal?
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How much heat will an instrument of 12 W produce in one minute if it is connected to the heat produced by it?
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The current passing through an electric kettle has been doubled. The heat produced will become:
(a) half
(b) double
(c) four time
(d) one-fourth
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(a) thin and short
(b) thick and short
(c) low melting point
(d) higher resistance than rest of wiring
Three heaters each rated 250 W, 100 V are connected in parallel to a 100 V supply. Calculate:
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Give scientific reason :
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Find the odd one out and give its explanation.
Write scientific reason.
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Explain the importance/uses of fuse wire.
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The following is not a safety device.
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Mass of the coated object in g |
| A | Nail | 3.0 | 3.15 |
| B | Thin plate | 6.0 | 6.33 |
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She wrote: Three-pin connections reduce heating of connecting wires.
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