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प्रश्न
State two advantages of filling an inert gas in an evacuated electric filament lamp.
उत्तर
(i) The inert gas is filled at very low pressure to prevent oxidation as well as evaporation and thus increases its life.
(ii) While bulb is working, a convection current is set-up within it which carries the spurting particles of tungsten upward towards the cap and hence the blackening of the lower part (transparent portion) of the bulb is avoided.
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संबंधित प्रश्न
What is the maximum power in kilowatts of the appliance that can be connected safely to a 13 A ; 230 V mains socket?
Write the formula for electric power in terms of potential difference and current.
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(a) 60 W
(b) 250 W
(c) 850 W
(d) 2000 W
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| Appliance | Current |
| Kettle | 8.5 A |
| Lamp | 0.4 A |
| toaster | 4.8 A |
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