2/10/2024 0 Comments What is entropy at absolute zeroLocated at: en./wiki/Third_l.thermodynamics. License: CC BY-SA: Attribution-ShareAlike Located at: en./wiki/Magnetic_refrigeration. Located at: en./wiki/Entropy.hermodynamics). License: CC BY-SA: Attribution-ShareAlikeĬC LICENSED CONTENT, SPECIFIC ATTRIBUTION At zero kelvin the system must be in a state with the minimum possible energy, thus this statement of the third law holds true if the perfect crystal has only one minimum energy state. demagnetization: The process of removing the magnetic field from an object. The third law of thermodynamics is sometimes stated as follows: The entropy of a perfect crystal at absolute zero is exactly equal to zero.degeneracy: Two or more different quantum states are said to be degenerate if they are all at the same energy level.The total absence of heat the temperature at which motion of all molecules would cease. absolute zero: The coldest possible temperature: zero on the Kelvin scale and approximately -273.15☌ and -459.67☏.microstate: The specific detailed microscopic configuration of a system.Right: An infinite number of steps is needed since S(0,X1)= S(0,X2). Left side: Absolute zero can be reached in a finite number of steps if S(T=0,X1)≠S(T=0, X2). Horizontal lines represent isentropic processes, while vertical lines represent isothermal processes. However, going back to the third law, at T=0 there is no entropy difference, and therefore an infinite number of stepswould be needed for this process (illustrated in ).Ĭan Absolute Zero be Reached?: Temperature-Entropy diagram. )Īssuming an entropy difference at absolute zero, T=0 could be reached in a finite number of steps. The parameter X in this case would be the magnetization of the gas. As an example, one can think of a multistage adiabatic magnetization-demagnetization cycle setup where a magnetic field is switched on and off in a controlled way.
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