Physics - Heat & Thermo Question with Solution | TestHub

According to Stefan's law $$E=\sigma T^4$$ Heat radiated per unit area in 1 hour ( $3600\mathrm{s})$ is $$=5.7\times 10^{-8}\times (300{)}^4\times 3600=1.7\times 10^{10}\mathrm{J}$$