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An electric heater emits 1000W of therma...

An electric heater emits 1000W of thermal radiation. The coil has a surface area of `0.02m^(2)` . Assuming that the coil radiates like a blackbody, Find its temperature. `sigma=6.0xx10^(-8)Wm^(-2)K^(-2)` .

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Let the temperature of the coil be T. The coil will emit radiation at a rate AsigmaT^(4)` . Thus, `1000W=(0.020m^(2)xx(6.0xx10^(-s)Wm^(-2)K^(-4)xxT^(4)` . Or, `T^(4)=(1000)/(0.020xx6.00xx10^(-s))K^(4)` . `=8.033xx10^(11)K^(4)` . Or, `T=995K` .
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