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प्रश्न
What would happen and why, to an electric bulb when it is connected across a supply of voltage (i) lower (ii) higher than its proper rating?
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उत्तर
We know, Current = Voltage/Resistance
For a given bulb, the filament would have a definite characteristic resistance. Hence
(i) When the bulb is connected to a lower voltage supply, it would draw less current than its ‘proper current’. Hence it would not glow to its full capacity.
(ii) When the bulb is connected to a higher voltage supply, it would draw more current than its ‘proper current’. Hence its filament would get heated to a temperature higher than its proper permitted limit and is, therefore, likely to melt or fuse.
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| Sr.no. | Name | Nos. | Power rating | Time/day |
| 1 | Bulb | 4 | 100 W | 7.5 hr |
| 2 | Fans | 2 | 50 W | 10 hr |
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| 4 | Iron | 1 | 500 W | 1 hr |
| 5 | Electric stove | 1 | 750 W | 2 hr |
