Chapter 2 - Energy, Energy Transfer, and General Energy Analysis - Problems - Page 99: 2-39

$U_{2}=35.5kJ$

$W_{in}=500Nm=500J=0.5kJ$ Applying the energy balance: $E_{in}-E_{out}=\Delta E_{system}$ $Q_{in}+W_{in}-Q_{out}-W_{out}=U_{2}-U_{1}$ $30kJ+0.5kJ-5kJ-0kJ=U_{2}-10kJ$ Solving for $U_{2}$: $U_{2}=30kJ+0.5kJ-5kJ+10kJ=35.5kJ$