First Law of Thermodynamics

  • It’s the law of conservation of energy
  • Change in total energy of the system is compensated by an equal and opposite change in the total energy of the surroundings.






In many applications of the first law, the system undergoes no change in external potential or kinetic energy, but only changes in internal energy. For these non-flow processes, the first law becomes:

                                                 \( \Delta \)U = Q + W