Question about the thermodynamic temperature scale

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SUMMARY

The discussion centers on the relationship between absorbed and rejected heat in thermodynamic processes, specifically in isothermal conditions. It establishes that the heat transfer (dQ) can be equated to the work done (Pdv) during an isothermal process. The gas equation of state, P(v-b) = Rθ, is utilized to derive the temperature in Kelvin (θ) and its connection to the Carnot cycle's efficiency, defined as η = 1 - Tc/Th. The first law of thermodynamics is applied to relate heat capacities and temperature differences in the context of the Carnot cycle.

PREREQUISITES
  • Understanding of the first law of thermodynamics
  • Familiarity with the Carnot cycle and its efficiency
  • Knowledge of gas equations of state, specifically P(v-b) = Rθ
  • Concept of heat capacities, particularly CV
NEXT STEPS
  • Study the derivation of the Carnot cycle efficiency and its implications
  • Explore the applications of the first law of thermodynamics in various thermodynamic processes
  • Investigate the relationship between heat capacity and temperature in different states of matter
  • Learn about isothermal processes and their significance in thermodynamic systems
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Students and professionals in physics and engineering, particularly those focusing on thermodynamics, heat transfer, and energy efficiency in thermal systems.

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}##
1706566849802.png

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.
 
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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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