Undergraduate Student Seeking Answers on Sustaining Entropy

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In summary: Entropy refers to a measure of how much disorder or chaos is present in a system. In thermodynamics, the second law of thermodynamics states that entropy will always increase over time in a closed system. This is because the entropy is a measure of how much energy is in a system that is not being used to do work. This is why entropy can increase when we heat things up, or when we use machines that only use reversible reactions. However, it is possible to decrease entropy in a closed system by using processes that are adiabatic. This means that the energy is transferred without causing any heat or work to be created.
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TheoPan
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Hello everyone!

I am an undergraduate student from Greece in my first semester of Mechanical Engineering, but I am fascinated with physics. I've been studying some physics books from my university's library and reached the chapter of entropy. I understand the 2nd law of thermodynamics but what would happen if we could sustain entropy at the same level over time? Is it possible? Would it be possible in the future?

Thank you in advance!
 
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A reversible reaction is one that does not increase the entropy. A machine only using reversible reactions will keep the same entropy. But this really limits what you can do.
An irreversible reaction increases entropy. Your body has a bunch of irreversible reactions, so entropy overall will increase.
 
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Khashishi said:
A reversible reaction is one that does not increase the entropy. A machine only using reversible reactions will keep the same entropy. But this really limits what you can do.
An irreversible reaction increases entropy. Your body has a bunch of irreversible reactions, so entropy overall will increase.
Can you please state this more precisely, like, for example, with respect to the entropy of the universe rather than the entropy of a specific (closed) system?
 
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I guess it depends on what the OP is asking. If they are asking if it's possible to keep the entropy of the whole universe at a fixed level, then the answer is no. But for a small, carefully designed closed system, the second law only prohibits the entropy from going down. It is allowed to stay at the same level. For a macroscopic sized system, there's always some non-idealities, so you can't really prevent entropy from increasing. As a MechE, you will certainly learn about adiabatic processes, which are idealizations, but they are useful to study since we can get close, and they teach us the fundamental limits on what is possible.
 
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Khashishi said:
I guess it depends on what the OP is asking. If they are asking if it's possible to keep the entropy of the whole universe at a fixed level, then the answer is no. But for a small, carefully designed closed system, the second law only prohibits the entropy from going down. It is allowed to stay at the same level. For a macroscopic sized system, there's always some non-idealities, so you can't really prevent entropy from increasing. As a MechE, you will certainly learn about adiabatic processes, which are idealizations, but they are useful to study since we can get close, and they teach us the fundamental limits on what is possible.
I think that we have a bit of a terminology issue here. Physicists call a "closed system" one for which no mass enters or leaves, and no work or heat transfer takes place at the boundaries; however, this is what engineers refer to as an "isolated system." Engineers call a "closed system" one for which no mass enters or leaves, but for which work and heat transfer can take place at the boundaries. Under this engineering definition of a closed system, entropy can certainly decrease for certain processes.

Chet
 

1. What is entropy and why is it important?

Entropy is a measure of the disorder or randomness of a system. In scientific terms, it is a thermodynamic quantity that describes the amount of energy that is unavailable for work in a given system. It is important because it helps us understand the natural processes and changes that occur in the universe.

2. How does entropy affect sustainability?

Entropy plays a crucial role in sustainability as it is a measure of the amount of energy that is lost in a system. As entropy increases, the efficiency of a system decreases, making it more difficult to sustain and maintain. This is why it is important to find ways to reduce entropy and increase efficiency in order to promote sustainability.

3. Can entropy be reversed?

In isolated systems, entropy can never decrease, as stated by the second law of thermodynamics. However, in open systems, entropy can be reduced by adding energy and information to the system. This is why sustainable practices focus on reducing entropy and increasing efficiency.

4. How can we sustain entropy in our daily lives?

There are several ways to sustain entropy in our daily lives, such as reducing energy consumption, recycling and reusing materials, using renewable energy sources, and promoting sustainable practices. By reducing the amount of energy lost in our daily activities, we can help sustain entropy and promote a more sustainable future.

5. What is the role of undergraduate students in sustaining entropy?

Undergraduate students play a vital role in sustaining entropy by learning about and promoting sustainable practices. By studying and researching ways to reduce entropy, students can contribute to the development of sustainable technologies and practices. Additionally, students can also lead by example and promote sustainable habits in their daily lives, thus helping to sustain entropy and promote a more sustainable future.

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