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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.
RELATED QUESTIONS
An electric bulb is rated 220 V and 100 W. When it is operated on 110 V, the power consumed will be ______.
The SI unit of energy is :
(a) joule
(b) coulomb
(c) watt
(d) ohm-metre
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(a) 100 J
(b) 600 J
(c) 3600 J
(d) 6000 J
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