[عاطف خليفة]

0. If two systems are in thermal equilibrium with a third system, then they must be in thermal equilibrium with each other. 1. , where dE is the energy change, is the change in heat, dW is the work done, T is the temperature, dS is the change in entropy, P is the pressure, and dV is the volume change. 2. The second law of thermodynamics prohibits the construction of a perpetual motion machine of `the second kind.' A consequence is the result that . 3. As temperature goes to 0, the entropy S approaches a constant . Combining the first and second laws gives the combined law of thermodynamics