B How are thermodynamic laws related to one another?

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The discussion centers on the interconnections between the laws of thermodynamics, particularly the zeroth, first, and second laws. The zeroth law establishes thermal equilibrium, indicating that if two bodies are in contact with a third body at the same temperature, they share that temperature. The first law emphasizes energy conservation, stating that energy remains constant during conversion. The second law addresses the direction of heat transfer, asserting that heat flows from hotter to cooler bodies, which relates to the zeroth law through the concept of thermal equilibrium. The conversation seeks to clarify the relationships among these laws, suggesting that they are interconnected rather than entirely independent.
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Would you please explain how the laws of thermodynamics are related to one another? Are the laws entirely independent of one another?
I can see only a connection between the zeroth law and the second law. Following is the quote from my previous thread.

1. Zeroth law: The zeroth law of thermodynamics states that when two bodies have equality of
temperature with a third body, they in turn have equality of temperature with each other (sonntag\borgnakke)

2. First law: The First Law states that whenever energy is converted in form, its total quantity remains unchanged (www.soas.ac.uk)

3a. Second Law (Kelvin-Planck Statement): The Kelvin–Planck statement: It is impossible to construct a device that will operate in a cycle and produce no effect other than the raising of a weight and the exchange of heat with a single reservoir (sonntag\borgnakke)

3b. Second Law (Clasius Statement): It is impossible to construct a device that operates in a cycle and produces no effect other than the transfer of heat from a cooler body to a warmer body (sonntag\borgnakke)

Following is the quote from my previous thread.
256bits said:
the temperature difference is the part of the second law of thermodynamics - hotter things cool down, cooler things do not heat up - spontaneously.
https://www.physicsforums.com/threads/how-accurate-is-the-definition-of-heat.1045265/

So can we say that the zeroth law is the result of the second law? Is this true? Are there reason-and-result relations in laws of thermodynamics?
 
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It is how are universe works, and for that reason they are inteconnected.
Zoroth law would be about equilibrium.
The first law is a statement about conservation of energy.
The second law is about what - possibly about the availablity of work.
 
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But we can make a clear statement about the connection between zeroth law and the second law as

"The heat flows from the higher temperature object to lower temperature object so two objects comes to the same temperature if they are in contact". Does this statement not join clearly the zeroth law and the second law?

Can you make clear statements that clarify the relations between "zeroth law and first law", "first law and the second law"?

Than you.
 
Possibly useful:
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/thereq.html
There are underlying ideas about heat associated with the zeroth law of thermodynamics,
and one of those ideas was expressed by Maxwell as "All heat is of the same kind."

If A is in thermal equilibrium with B,
then every unit of internal energy that passes from A to B is balanced
by the same amount of energy passing from B to A.

This is true even if the atomic masses in A are different from those in B, and
even if the amount of energy per unit mass in A is different because the material has a different specific heat.

This implies that there is a measurable property
that can be considered to be the same for A and B,
a property upon which heat transfer depends. That property is called temperature.

http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw2.html
especially the catchy formulation:
If the first law of thermodynamics says you can't win,
then the Second Law of Thermodynamics says you can't even break even.

The First Law is essentially a statement of conservation of energy
and asserts that you can't get more energy out of a heat engine than you put in.

But the Second Law says that no heat engine can use all the heat produced by a fuel to do work
 
mech-eng said:
But we can make a clear statement about the connection between zeroth law and the second law as

"The heat flows from the higher temperature object to lower temperature object so two objects comes to the same temperature if they are in contact". Does this statement not join clearly the zeroth law and the second law?

Can you make clear statements that clarify the relations between "zeroth law and first law", "first law and the second law"?

Than you.
No,
 
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