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Reason for 2nd law of thermodynamics and evolution


URAIN

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The second law of thermodynamics expresses that things tends to go from order to disorder as time progresses.

No, it does not. What is says is that every real thermodynamic process results in a change in entropy greater than or equal to zero.

 

1) What is the reason for ....increase in entropy.... according to second law of thermodynamics?

There are more microstates available to the system after the process than before.

Edited by chilehed
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Of course -1 exists. If you wanted, you can plug in some imaginary numbers in there. :)

 

The second law of thermodynamics must be violated billions of time. This is not a statement of evolutionist else it is statement of "Pseudo Evolutionists" ( Objection

may posted with proof of scientific rules

 

not true. none of the physical principles are violated.

 

You are not giving response to my questionssad.gif

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You can also take different sized of marbles and do the same experiment, and the shaking will sort the marbles, with the largest on top, even if they are more massive (the popcorn or Brazil-nut effect).

Ok, I admit that the marbles were a poor example. Still, the random motion of molecules is one of the reasons for disorder, especially for gas phase systems. Obviously, if you know more about it, then the random motion is far from the only phenomenon involved. All kinds of attractions between particles make the motions less random (especially in liquids and reactions), and these influence the mixing behavior. But it's pretty difficult to explain entropy when you take an example of a system that actually ends up demixing itself (e.g. oil and water), which is why I didn't choose it as an example. Of course, the laws of thermodynamics still count. Entropy still increases... but it's a lot more difficult to understand.

 

Damn, it's always a thin rope you're walking in this forum. Oversimplify, and you get (rightly) corrected by others. But make it too complicated and others just fail to understand it. I figured the level in this thread was that of high school, so I chose to approach it in a simple way. It might have been a wrong approach.

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Ok, I admit that the marbles were a poor example. Still, the random motion of molecules is one of the reasons for disorder, especially for gas phase systems. Obviously, if you know more about it, then the random motion is far from the only phenomenon involved. All kinds of attractions between particles make the motions less random (especially in liquids and reactions), and these influence the mixing behavior. But it's pretty difficult to explain entropy when you take an example of a system that actually ends up demixing itself (e.g. oil and water), which is why I didn't choose it as an example. Of course, the laws of thermodynamics still count. Entropy still increases... but it's a lot more difficult to understand.

 

Damn, it's always a thin rope you're walking in this forum. Oversimplify, and you get (rightly) corrected by others. But make it too complicated and others just fail to understand it. I figured the level in this thread was that of high school, so I chose to approach it in a simple way. It might have been a wrong approach.

 

Your example was fine. I just wanted to point out that the situation is not as straightforward as the OP implies. The local entropy of the box can decrease; all that means is there an increase somewhere else.

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Please clear (I have not understood fully), what you are saying?

 

All engines reject the heat(energy)

 

1) How much rejects ?

 

2) Why it rejects ?blink.gif

 

An engine cannot fully convert heat into mechanical work. That's one way of stating the second law. How much rejected heat depends on the details, but one cannot cannot exceed the efficiency of the Carnot cycle.

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/carnot.html

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An engine cannot fully convert heat into mechanical work. That's one way of stating the second law. How much rejected heat depends on the details, but one cannot cannot exceed the efficiency of the Carnot cycle.

http://hyperphysics....rmo/carnot.html

 

 

Is there no answer, why it rejects the heat ? (Why engine cannot fully convert heat into mechanical work)

 

Is there any research are going on to find that? (Our teacher was told that this is a researching subject)unsure.gif

 

 

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Is there no answer, why it rejects the heat ? (Why engine cannot fully convert heat into mechanical work)

 

Is there any research are going on to find that? (Our teacher was told that this is a researching subject)unsure.gif

 

There is an answer: the second law of thermodynamics. Much of the research into it occurred more than a century ago, when thermodynamics was being established.

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You can also take different sized of marbles and do the same experiment, and the shaking will sort the marbles, with the largest on top, even if they are more massive (the popcorn or Brazil-nut effect).

 

No, it doesn't — entropy can't decrease for isolated systems but that's not true in general — and no, they don't. Straw man.

 

All engines have to reject heat.

 

 

Here you have given the example for the question, what is the reason for disorder according to 2nd law of thermodynamics.

 

Other side you have said

An engine cannot fully convert heat into mechanical work. That's one way of stating the second law. How much rejected heat depends on the details, but one cannot cannot exceed the efficiency of the Carnot cycle.

http://hyperphysics....rmo/carnot.html

 

Your example of marbles, where shows, the reason for Engine fully not converting heat into mechanical work?

 

Marbles are not gone outside of the bucket. But in the engine we dont know heat,

 

A) where it gone?

B) Why it gone?

C) Do we have not to question the law ? By the word 'why'?

 

 

 

Edited by URAIN
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Here you have given the example for the question, what is the reason for disorder according to 2nd law of thermodynamics.

 

Other side you have said

 

 

Your example of marbles, where shows, the reason for Engine fully not converting heat into mechanical work?

 

Marbles are not gone outside of the bucket. But in the engine we dont know heat,

 

A) where it gone?

B) Why it gone?

C) Do we have not to question the law ? By the word 'why'?

 

In the marble example there is work done on the system — it is not isolated. The entropy increase occurs elsewhere, which is why it is pertinent to the evolution claim.

 

The rejected heat goes outside of the system in question. Because the entropy has to increase. Question it, but try and develop an understanding of it first. Physics texts contain example of what the implications are of violating the law and how we know it holds. Many involve spontaneous motion or energy transfer of some kind, in systems where it is not observed and even a crackpot would not expect to observe it.

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In the marble example there is work done on the system — it is not isolated. The entropy increase occurs elsewhere, which is why it is pertinent to the evolution claim.

 

The rejected heat goes outside of the system in question. Because the entropy has to increase. Question it, but try and develop an understanding of it first. Physics texts contain example of what the implications are of violating the law and how we know it holds. Many involve spontaneous motion or energy transfer of some kind, in systems where it is not observed and even a crackpot would not expect to observe it.

 

Thanks

 

I heard that light travels continuously. If we consider it as an energy, it also has an end, when we apply this law (energy changes from order to disorder).

 

what you say about this? (I think You understand, what I am saying)

 

While answering, pls you have to consider Redshift also.

 

 

 

 

 

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Thanks

 

I heard that light travels continuously. If we consider it as an energy, it also has an end, when we apply this law (energy changes from order to disorder).

 

what you say about this? (I think You understand, what I am saying)

 

While answering, pls you have to consider Redshift also.

 

A single photon traveling, even with a redshift, represents a reversible process. There should be no change in entropy. I don't see how a single photon can represent "disorder" even if we use that crude measure. A continuously-traveling (i.e. non-interacting) photon has one state it can be in.

 

Once you add interactions, then you can see an increase in entropy. A laser has photons in the same state, or at least a small set of states. Low entropy. After scattering or absorption/emission, there are many possible states. Entropy has increased. (That's the thermodynamic explanation of laser cooling; you'd look at the Gibbs or Helmholtz free energy)

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A single photon traveling, even with a redshift, represents a reversible process. There should be no change in entropy. I don't see how a single photon can represent "disorder" even if we use that crude measure. A continuously-traveling (i.e. non-interacting) photon has one state it can be in.

 

Once you add interactions, then you can see an increase in entropy. A laser has photons in the same state, or at least a small set of states. Low entropy. After scattering or absorption/emission, there are many possible states. Entropy has increased. (That's the thermodynamic explanation of laser cooling; you'd look at the Gibbs or Helmholtz free energy)

 

You mean light from the stars travels continuously to the infinite.

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Light that does not interact travels continuously.

 

In night assume there is no power then we lighten a torch then we see light. After some time we off the torch then we cannot see the light.

 

As per your answer, reason for not seeing the light may it light may be traveled far distance. How you analyze it?

 

 

 

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In night assume there is no power then we lighten a torch then we see light. After some time we off the torch then we cannot see the light.

 

As per your answer, reason for not seeing the light may it light may be traveled far distance. How you analyze it?

 

You only see light that hits your eyes, not light that doesn't. You can't see light shined away from you that has not scattered off of something.

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You only see light that hits your eyes, not light that doesn't. You can't see light shined away from you that has not scattered off of something.

 

Do we see light from any device (after off of torch) ? name the Device please.

 

 

 

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Do we see light from any device (after off of torch) ? name the Device please.

 

You can't see the light if it's not going into your eye. If you shine a light out into space and turn it off, the photons are a distance ct away after a time t. You can't see them. But we can see them if they scatter off of something, which is why we can see the moon and planets — that's light that has come from the sun. If the planets aren't there, the light just keeps on going.

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You can't see the light if it's not going into your eye. If you shine a light out into space and turn it off, the photons are a distance ct away after a time t. You can't see them. But we can see them if they scatter off of something, which is why we can see the moon and planets — that's light that has come from the sun. If the planets aren't there,

 

 

the light just keeps on going.

 

(I think you will not get bored or you will not get problems from my question and this is discussion forum therefore we can discuss)

 

1) Light is a energy, as like this, sound also energy. If we observe sound it will not contain same efficiency at far distance (another point where it is moved).

 

2) If we consider moving as work then work needs a energy and work will not continuously (until it will not get energy there is no work).

Light is moving from one point to another,

which has made to move the light?

 

Movement is a work from energy and when work has made then energy will to end ( energy transformed into work). what you say.

 

 

 

 

 

Edited by URAIN
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(I think you will not get bored or you will not get problems from my question and this is discussion forum therefore we can discuss)

 

1) Light is a energy, as like this, sound also energy. If we observe sound it will not contain same efficiency at far distance (another point where it is moved).

 

2) If we consider moving as work then work needs a energy and work will not continuously (until it will not get energy there is no work).

Light is moving from one point to another,

which has made to move the light?

 

Movement is a work from energy and when work has made then energy will to end ( energy transformed into work). what you say.

 

Light has energy and the intensity of a point source does drop off as 1/r^2, but the surface area goes up as r^2. The total energy remains constant.

 

Movement at constant velocity does not require work to maintain it if there are no external forces. You only need energy to start the motion.

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Light has energy and the intensity of a point source does drop off as 1/r^2, but the surface area goes up as r^2. The total energy remains constant.

 

Movement at constant velocity does not require work to maintain it if there are no external forces. You only need energy to start the motion.

 

Thanks. I will see about it.

 

What about sound. We listen sound low at far distance from its origin position.

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