The operating temperatureof a tungsten filament in an incandescent light bulb is 2450 K, and itsemissivity is 0.350. Find the surface area of the filament of a 150 Wbulb if all the electrical energy consumed by the bulb is radiated by thefilament as electromagnetic waves. (Only a fraction of the radiation appearsas visible light.)

The operating temperatureof a tungsten filament in an incandescent light bulb is 2450 K, and itsemissivity is 0.350. Find the surface area of the filament of a 150 Wbulb if all the electrical energy consumed by the bulb is radiated by thefilament as electromagnetic waves. (Only a fraction of the radiation appearsas visible light.)

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