Problem

A 1.0 kg bar of copper is heated at atmospheric pressure (

1.01 \times 10^5 \text{ N/m}^2

). If its temperature increases from

20^\circ\text{C}

50^\circ\text{C}

, calculate the change in its internal energy.

\alpha = 7.0 \times 10^{-6} / ^\circ\text{C}

\rho = 8.92 \times 10^3 \text{ kg/m}^3

and

c = 387 \text{ J/kg}\cdot^\circ\text{C}