Physics

Problem

A tungsten filament is modeled as a cylindrical surface of length

5.0\,\text{cm}

and radius

4.0\,\text{mm}

. The filament’s emissivity is

0.30

, and it radiates

60\,\text{W}

of thermal energy in steady operation. Taking

\sigma = 5.67\times10^{-8}\,\text{W}\,\text{m}^{-2}\,\text{K}^{-4}

, calculate the filament’s operating temperature.