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Question
Why is a concave reflector placed behind the heating element in a room heater.
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Solution
The concave reflector, reflects the heat radiations in the forward direction. Thus, large amount of heat radiations are available in one particular direction.
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| Appliance | Current |
| Kettle | 8.5 A |
| Lamp | 0.4 A |
| toaster | 4.8 A |
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