Is a Freezer Truly a Closed System?

In summary, the conversation discusses the topic of entropy and whether or not the universe can be considered a truly closed system. The concept of a freezer and its energy source is also brought up. It is mentioned that while a truly closed system may not exist, it is still possible to analyze and understand the behavior of such a system. The conversation also touches on the idea of recycling energy and the relationship between work and heat.
  • #1
DonkeyMaHonkey
3
0
I have read quite a few discussions about this topic of entropy and if this universe has a truly closed or, as I prefer to describe it "undisturbed", system and I have read some discussions about a freezer and chilling ice cubes etc. etc... To my extent of reading these conversations no one has addressed the actual energy source of the freezer which is the plug in the wall which comes from an external system. Any comments?
 
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  • #2
I'm not really sure what you are talking about. Indeed a freezer is not a closed system...
 
  • #3
Agreed. Maybe you can help me, please. What should be a law of physics...do not trust the internet! ;)
Anyway, I was just reading on how people say the 2nd law only works for a closed system; yet the Earth is not closed nor anything else in reality, so how can this be a "law"? There is no true vacuum, if you dig string or most quantum theories, and biology seems to go in the opposite direction. And a star's energy from across the galaxy to conveniently set the universe at net zero doesn't float because a universe that is net zero would not be unstable enough to expand. Please respond.
 
  • #4
You are right that there can be no such thing as a truly closed system, because there's always going to some energy leaking into or out of the system. However, that doesn't prevent us from mathematically analyzing how such a system would behave if we could construct one, and that's where the law comes from.

It is possible to construct systems in which the energy leakage in or out is small enough to ignore. These act so much like the truly closed systems that we cannot build that we can use the closed system math on them.
 
  • #5
I guess that makes sense. Thank you.
 
  • #6
A closed system could maybe have a way of a recycle energy method instead of needing an outside source.
 
  • #7
With respect to the freezer, yes, it is not a closed system. If it were, then it would not be able to freeze (separating heat from not-heat requires work). How ever, since you know that that is true, then you also know that everything that enables that work to get done has to come in through that small black wire, so you can study the relationship between the cold (not temperature, but heat capacity, or lack of it) and what the wire is doing. Without the law, you have no way of knowing there has to be an exclusive relationship. That's how the relationship between a horse working turning a cannon drill and the heat given off by the work were related.
 

1. What is the second law of thermodynamics?

The second law of thermodynamics states that the total entropy of an isolated system (a system that does not exchange energy or matter with its surroundings) will always tend to increase over time. This means that energy will spontaneously flow from high to low concentrations, resulting in an increase in disorder or randomness within the system.

2. How does the second law of thermodynamics apply to freezers?

The second law of thermodynamics applies to freezers by dictating that energy will flow from the warmer surroundings (the room) into the colder environment (the freezer) in order to maintain equilibrium. This is why the inside of a freezer is colder than the room temperature, as the energy is being removed from the freezer to maintain a lower temperature.

3. Why is it difficult to achieve absolute zero in a freezer?

Absolute zero is defined as the lowest possible temperature, at which all molecular motion stops. According to the second law of thermodynamics, it is impossible to reach absolute zero as it would require removing all energy from a system, which is not possible. In a freezer, the energy is constantly being removed, but it can never reach absolute zero.

4. Can the second law of thermodynamics be violated?

No, the second law of thermodynamics is a fundamental law of physics and cannot be violated. It has been observed and tested in countless experiments and is a crucial principle in understanding the behavior of energy and matter in the universe.

5. How does the second law of thermodynamics affect the efficiency of a freezer?

The second law of thermodynamics plays a role in the efficiency of a freezer by dictating that some energy will always be lost during the cooling process. This is because no system can have 100% efficiency, and some energy will inevitably be converted into heat and lost. This is why most freezers have an energy efficiency rating, to indicate how much energy is being lost during the cooling process.

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