Question about the thermodynamic temperature scale

AI Thread Summary
The discussion centers on the relationship between absorbed and rejected heat in an isothermal process, questioning whether it can be equated to the work done, represented by dQ = Pdv. The reasoning presented involves the first law of thermodynamics and the Carnot cycle to establish that the efficiency of the cycle leads to the conclusion that temperature θ equals absolute temperature T. The gas equation of state and the dependence of heat capacity on temperature are also highlighted. The inquiry seeks validation of the assertion that absorbed or rejected heat equals work done during isothermal conditions. Overall, the analysis aims to clarify the thermodynamic principles governing these relationships.
MatinSAR
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Homework Statement
Prove the equality of ideal gas and thermodynamics temperature for a specific gas.
Relevant Equations
##\dfrac {Q_1}{Q_2}= \dfrac {T_1}{T_2}##
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My first problem is to find the absored and rejected heat. Can I say that it is equal to the work done in an isothermal proccess (##dQ=Pdv##)?

My reasoning : We have ##dQ=C_V d\theta + Pdv##. For constant temperature it becomes :$$dQ=Pdv$$
 
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The gas equation of state is expressed as P(v-b) = Rθ, where P is pressure, v is specific volume, b is a constant, R is the gas constant, and θ is temperature in Kelvin. The heat capacity, CV, depends only on temperature θ. To demonstrate θ = T, we use the Carnot cycle. In this cycle, efficiency (η) is given by 1 - Tc/Th, where Tc is the cold reservoir temperature and Th is the hot reservoir temperature.

In a Carnot cycle, efficiency is also expressed as 1 - Qc/Qh. Utilizing the first law of thermodynamics, we substitute Qc = CV(θc - θh) and Qh = CV(θh - θc) into the efficiency equation, solving for θ to find θ = T.
 
connectednatural said:
The gas equation of state is expressed as P(v-b) = Rθ, where P is pressure, v is specific volume, b is a constant, R is the gas constant, and θ is temperature in Kelvin. The heat capacity, CV, depends only on temperature θ. To demonstrate θ = T, we use the Carnot cycle. In this cycle, efficiency (η) is given by 1 - Tc/Th, where Tc is the cold reservoir temperature and Th is the hot reservoir temperature.

In a Carnot cycle, efficiency is also expressed as 1 - Qc/Qh. Utilizing the first law of thermodynamics, we substitute Qc = CV(θc - θh) and Qh = CV(θh - θc) into the efficiency equation, solving for θ to find θ = T.
This is another method to solve. Thanks for your reply ...
What's your idea about what I've said?
Can I say that the absored or rejected heat is equal to the work done in an isothermal proccess (##dQ=Pdv##)? Because we have ##dQ=C_V d\theta + Pdv##. For constant temperature it becomes :$$dQ=Pdv$$
 
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