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The operating temperature of a tungesten...

The operating temperature of a tungesten filament in an indandescent lamp is `2000 K ` and its emissivity is `0.3`.
Find the surface area of the filament of a `25` watt lamp. Stefan's constant ` sigma = 5.67xx10^(-8) Wm^(-2)K^(-4)`

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To find the surface area of the tungsten filament in a 25-watt incandescent lamp, we can use Stefan-Boltzmann's law, which relates the power radiated by a black body to its temperature and surface area. The formula is given by: \[ W = A \cdot \varepsilon \cdot \sigma \cdot T^4 \] Where: - \( W \) is the power (in watts), ...
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