Question about the thermodynamic temperature scale

  • #1
MatinSAR
524
174
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 :$$dQ=Pdv$$
 
Physics news on Phys.org
  • #2
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.
 
  • Like
Likes MatinSAR
  • #3
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 :$$dQ=Pdv$$
 

1. What is the thermodynamic temperature scale?

The thermodynamic temperature scale is a scale of temperature measurement based on the principles of thermodynamics, specifically the zeroth law of thermodynamics. It is defined in terms of the behavior of ideal gases and the concept of absolute zero.

2. How is the thermodynamic temperature scale different from other temperature scales?

The thermodynamic temperature scale is unique in that it is an absolute scale, meaning it is not dependent on the properties of any particular substance. Other temperature scales, such as the Celsius and Fahrenheit scales, are relative scales that are based on the properties of specific substances.

3. What is the significance of absolute zero on the thermodynamic temperature scale?

Absolute zero is the lowest possible temperature on the thermodynamic temperature scale, at which point the thermal motion of particles ceases. This temperature serves as the zero point of the scale, allowing for precise and consistent temperature measurements.

4. How is the thermodynamic temperature scale measured in practice?

The thermodynamic temperature scale is typically measured using devices such as thermometers or thermocouples, which can accurately determine the temperature of a substance based on its thermal properties. These measurements are then calibrated against known reference points on the scale.

5. What are the units used on the thermodynamic temperature scale?

The units used on the thermodynamic temperature scale are kelvin (K) or degrees Kelvin. The kelvin is defined as 1/273.16 of the triple point temperature of water, making it a precise and consistent unit of measurement for temperature on the absolute scale.

Similar threads

  • Introductory Physics Homework Help
Replies
14
Views
706
  • Introductory Physics Homework Help
Replies
8
Views
1K
  • Introductory Physics Homework Help
Replies
21
Views
1K
  • Introductory Physics Homework Help
Replies
1
Views
870
Replies
1
Views
646
  • Introductory Physics Homework Help
Replies
3
Views
134
Replies
3
Views
1K
  • Introductory Physics Homework Help
Replies
33
Views
1K
  • Introductory Physics Homework Help
Replies
2
Views
914
  • Introductory Physics Homework Help
Replies
3
Views
973
Back
Top