A circular fin of inner diameter \(20 \mathrm{~cm}\) and outer diameter of \(26 \mathrm{~cm}\) transfers heat from a small motor cycle engine. If the average engine surface temperature is \(112^{\circ} \mathrm{C}\) determine the temperature distribution along the fin surface. The thermal conductivity of the fin material is \(21 \mathrm{~W} / \mathrm{m}^{\circ} \mathrm{C}\) and the convective heat transfer coefficient between the fin and atmosphere is \(120 \mathrm{~W} / \mathrm{m}^{\circ} \mathrm{C}\). Assume a suitable atmospheric temperature.