A 100 W bulb has tungsten filament of total length 1-0 m and radius 4- 10 -5m- The emissivity of the filament is 0-8 and - -6-0- 10 -8 W m -2K 4- Calculate the temperature of the filament when the bulb is operating at correct wattage-

GivenP = 100 WI = 1.0 mr = 4 #215; 10^ 5 mAccording to Stephen's law P = eAσ T #8308; 100 = (0.8) #215; (3.14 #215; 4 #215; 10^ 5) ...

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Stefan-Boltzman's Law

A 100 W bul...

Question

A $100 W$ bulb has tungsten filament of total length $1.0 m$ and radius $4 \times 10^{- 5} m$ . The emissivity of the filament is $0.8$ and $σ = 6.0 \times 10^{- 8}$ $W m^{- 2} K^{4}$ . Calculate the temperature of the filament when the bulb is operating at correct wattage.

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2000 K

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= 5.67 \times 10^{- 4} c m^{- 2} K^{- 4}

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