Entropy is an important term and its definition varying from disorder to waste of energy to limiting factor of conversion of energy and work done can be given in term of entropy and tempetature.

But in some real life situations, like rpm of an engine or clock rate of a cpu. We observe that on increasing frequency, a system comes to halt or perform low. So, is frequency relates to entropy, how.

  • $\begingroup$ Entropy is a physical property of the material being processed, and depends on the state of the material, as determined by its temperature, pressure, and chemical composition. It is not directly related to the process imposed on the material, except insofar as it affects the temperature etc. $\endgroup$ Sep 29, 2022 at 11:21
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    $\begingroup$ All definitions of physical entropy are identical. Entropy always means dS=deltaQ_rev/T for reversible or dS>=dQ/T for irreversible processes. My general suggestion to those who want to use the term in a conversation or argument is "Don't, unless you understand whether your process is reversible or irreversible and you can actually tell what the reversible amount of heat in the system is as a function of temperature. Wait... does your system even have a (one) temperature? If not, then see physics.stackexchange.com/questions/253259/what-dsdq-t-mean". $\endgroup$ Sep 29, 2022 at 12:04
  • $\begingroup$ @Chet Miller: you mean to say that entropy is state function, so it depends upon variables and not on how that process takes place. So do you consider frequency as variable or not. Entropy is unused energy or waste of time or low performance because the same work with less entropy can be done in less time if system could be more utillized. Question is about as entropy of cyclic process is constant and do work quickly needs more rate of process, does this rate is arbitrary, which I say no. $\endgroup$ Oct 1, 2022 at 14:31
  • $\begingroup$ @FlatterMann 2: entropy is general term whose meaning is randomness or disorder in statistical, unused energy or direction of work in thermodynamics, wastage of bandwidth in communication or reducing the efficiency or less conversion into useful work in general. All mean similar, that it is bad for power but not so bad for energy. My question is in some way disrupt laws of thermodynamics because entropy is considered as state function and inclusion of frequency is against it. $\endgroup$ Oct 1, 2022 at 14:38
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    $\begingroup$ Frequency is not a state variable. You cannot characterize the state of a material by specifying the frequency of any process that the material is suffering. On the other hand, the rate at which entropy is generated can certainly depend on process parameters like frequency. I have no idea what you are talking about in the remainder of your response. $\endgroup$ Oct 2, 2022 at 3:22

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Entropy of a cyclic process is constant because work done on the system put into initial state where it has again available for energy unutilized due to entropy. So it's common belief that increase in entropy is not applicable for a system operating in cycles and closed.

But we know that from Boltzmann's entropy law for microstate gives entropy relation with its state and it's constant whether system is at thermal equilibirium or not. The relation is,$$s=k\ln W$$But we know that sum of all microstates constituting macrostate and the sum of entropy of all microstates is equal to entropy of macrostate $S$,$$S=\sum_i^Ns_i$$As entropy is related to probability, we understand this situation with case of probability. If a coin is tossed then probability of either face of coin is half and this becomes more clear if number of trials is more. Now either we tossed same coin many times unless it doesn't show any biasness, or we can say that there are large number of similar coins are tossed and number of times either face showed up is about half.

Similarly we can consider a complete cycle of a system as microstate and number of cycles or frequency per unit of time as macrostate, sum of all microstates. So either all microstates are equally probable if operated simultaneously in same condition, or they minutely change their state by change in temperature. In either case entropy of each cycle is summed up to total entropy in given amount of time. If there are $N$ cycles in per unit of time, then total entropy is,$$S=Ns$$where $s$ is entropy of each cycle. This shows that entropy changes or increase with number of cycles.


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