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The temperature of the tungsten filament...

The temperature of the tungsten filament of a 60 W electric bulb is T= 2000 K. Find the surface area ofthe filament. The emmissivity of the surface is e= 0.30. Neglect radiation received from surrounding. Take `sigma=5.7xx10^(-8)w//M^(2)k.`

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To find the surface area of the tungsten filament of a 60 W electric bulb, we can use Stefan's law, which states that the power radiated by a black body is given by the formula: \[ P = \sigma \cdot e \cdot A \cdot T^4 \] where: - \( P \) = power radiated (in watts) - \( \sigma \) = Stefan-Boltzmann constant (\( 5.7 \times 10^{-8} \, \text{W/m}^2 \cdot \text{K}^4 \)) - \( e \) = emissivity of the surface (given as 0.30) ...
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