Question:
The left end of a copper rod (length $=20 \mathrm{~cm}$, area of cross - section $=0.20 \mathrm{~cm}^{2}$ ) is maintained at $20^{\circ} \mathrm{C}$ and the right end is maintained at $80^{\circ} \mathrm{C}$. Neglecting any loss of heat through radiation, find (a) the temperature at a point $11 \mathrm{~cm}$ from the left end and (b) the heat current through the rod. Thermal conductivity of copper $=385 \mathrm{~W} / \mathrm{m}-{ }^{\circ} \mathrm{C}$.
Solution:
