Physics

Problem

During an experiment, a flat plate of area

0.50\,\text{m}^2

1000\,\text{K}

is found to radiate

1.4\times10^{4}\,\text{W}

of thermal energy. Determine the emissivity of the plate. \;(Use

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