The tungsten filament of an electric lamp has a length l = 0.25m and diameter d = 0.04 mm. The power rating is P = 100 W. Assuming the radiation from the filament to be eta=80% of that of a black body radiator at the same temperature, estimate the temperature of the filament. Stefan constant = 5.7 xx 10^(-8)W//m^(2)K^(4).

The tungsten filament of an electric lamp has a length l = 0.25m and d

1.	The tungsten filament of an electric lamp has a length l = 0.25m and diameter d = 0.04 mm. The power rating is P = 100 W. Assuming the radiation from the filament to be eta=80% of that of a black body radiator at the same temperature, estimate the temperature of the filament. Stefan constant = 5.7 xx 10^(-8)W//m^(2)K^(4).
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