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प्रश्न
Why is a concave reflector placed behind the heating element in a room heater.
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उत्तर
The concave reflector, reflects the heat radiations in the forward direction. Thus, large amount of heat radiations are available in one particular direction.
संबंधित प्रश्न
A bulb marked 12 V, 24 W operated on a 12 volt battery for 20 minutes. Calculate:
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