Yahoo Clever wird am 4. Mai 2021 (Eastern Time, Zeitzone US-Ostküste) eingestellt. Ab dem 20. April 2021 (Eastern Time) ist die Website von Yahoo Clever nur noch im reinen Lesemodus verfügbar. Andere Yahoo Produkte oder Dienste oder Ihr Yahoo Account sind von diesen Änderungen nicht betroffen. Auf dieser Hilfeseite finden Sie weitere Informationen zur Einstellung von Yahoo Clever und dazu, wie Sie Ihre Daten herunterladen.
Is this an apt summary of Maxwell's Demon/the Second Law?
Note that I am not a physics student and this is not for a physics class – it's for English, and I only need a basic working definition:
"Maxwell's Demon is part of a thought experiment which shows a hypothetical violation of the Second Law of Thermodynamics. This law states that "the entropy of a closed system can only increase" (OED) – in other words, any "system," be it a house party or the whole universe, must become increasingly disorderly until it reaches a state of equilibrium and simply "stops."
The Maxwell's Demon thought experiment hypothetically violates this law. A "demon" sits in between two rooms which hot and cold particles are bouncing between, becoming more disorderly and eventually reaching a state of equilibrium. The demon, however, opens and closes a door between these rooms, keeping the hot and cold particles separate and thus decreasing the entropy of this system in violation of the Second Law."
Thank you!
Brian: doesn't the entropy decrease? At first, the hot and cold particles are bouncing randomly between rooms – the whole system is the same temperature. The demon begins separating them, and one room is hot and the other cold. Or do I have a faulty understanding of the whole thing?
Also, the house party is a reference to the story about which I'm writing – Thomas Pynchon's "Entropy," in which the scenario is represented by a house party.
3 Antworten
- ZardozLv 7vor 9 JahrenBeste Antwort
I think the function of the demon is a bit vague. He allows particles with a greater than average velocity to pass in one direction and particles with a less than average velocity to pass in the other. The demon isn't keeping them separate but separating them.
.
Quelle(n): [n] = 10ⁿ I'm promoting this as a convention. I encourage you all to join me. It's fast, it's fun and it's free. - BrianLv 6vor 9 Jahren
Cool never heard of that one. NOTE: the house party example is not a closed system. Closed system means that niether mass nor energy can flow through the boundaries of the system.
Hopefully i understand the demon idea:
The entropy of the system in your case did not decrease. All that happened is that the entropy stopped increasing. The second law says that entropy must increase for a closed system but it doesnt say a what rate it can change. In your case the rate is very slow. In this case the change in entropy can be considered 0. meaning it doesnt not change.
- Lee Wang TuiLv 7vor 9 Jahren
Entropy in closed system may increase or decrease. However entropy for PERFECT INSULATED system (our universe as system for an example) will always increase.
