# Answer Processes in T-V Diagram: A, E, C Explained

• suspenc3
In summary, the conversation discusses the expansion of an Ideal monatomic gas from initial volume V_0 to volume 2V_0 by five different processes. The question is asked to identify which process is isothermal, isobaric, or adiabatic. The answer is given that AE is isothermal as the initial and final temperatures are the same, AC is isobaric as the pressure remains constant, and AE is adiabatic as no heat flows in or out of the system. It is also mentioned that the entropy of the gas decreases in the adiabatic process, but the answer for d.) is not provided as the diagram is necessary to determine heat flow.

#### suspenc3

An Ideal monatomic gas at initial temperature $$T_0$$ (in Kelvins) expands from initial volume $$V_0$$ to volume $$2V_0$$ by each of the 5 processes indicated in the T-V diagram. In which process is the expansion a.)isothermal, b.) isobaric or c.)adiabatic? Explain your answers.
d.) In which process does the entropy of the gas decrease.

So far I've said that AE is isothermal, initial and final temperatures are the same.

AC is isobaric, Pressure remains constant

AE is adiabatic, no heat flows in or out of the sytem

Is this right?

I don't know what to do for d.)...

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huh? Could you restate the question.

wow, sorry. I don't know how that happened? I only hit reply once.

*edit* problem resolved

Is adiabatic expansion a heating or cooling process?

See edited original post and Attachment.

suspenc3 said:
An Ideal monatomic gas at initial temperature $$T_0$$ (in Kelvins) expands from initial volume $$V_0$$ to volume $$2V_0$$ by each of the 5 processes indicated in the T-V diagram. In which process is the expansion a.)isothermal, b.) isobaric or c.)adiabatic? Explain your answers.
d.) In which process does the entropy of the gas decrease.

So far I've said that AE is isothermal, initial and final temperatures are the same.

AC is isobaric, Pressure remains constant

AE is adiabatic, no heat flows in or out of the sytem

Is this right?
I can't see your diagram yet, but I expect there are 3 choices: a horizontal line (T = constant), a curve where T/V = constant and a curve that goes below that (lower final T) where $T/V^{\gamma-1}$ = constant. I think you can determine from that whether your answers are right.
I don't know what to do for d.)...
For adiabatic dS = dQ/T = 0. But for the others, which way does the heat flow?

AM

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If volume increases and temperature remains constant, dU does not change but the system does work (dW = PdV). So what can you say about dQ? What is the condition for dQ if it is adiabatic?

AM

## 1. What is the purpose of using a T-V diagram in scientific research?

The T-V diagram, also known as a temperature-volume diagram, is commonly used in thermodynamics to visually represent the changes in temperature and volume of a system. It helps scientists understand the behavior and properties of gases, liquids, and solids under different conditions.

## 2. How does the A-E-C process work in a T-V diagram?

The A-E-C process, also known as the adiabatic, isothermal, and isochoric processes, refers to the three types of paths that can occur on a T-V diagram. The adiabatic process is when there is no heat exchange between the system and its surroundings, the isothermal process is when the temperature remains constant, and the isochoric process is when the volume remains constant.

## 3. What do the lines on a T-V diagram represent?

The lines on a T-V diagram represent the different thermodynamic processes that a system can undergo. The slope of the line determines the relationship between temperature and volume, and the area under the line represents the work done by the system.

## 4. How can T-V diagrams be used to calculate the efficiency of a system?

T-V diagrams can be used to calculate the efficiency of a system by determining the area under the curve of the process and dividing it by the total area of the diagram. This ratio represents the fraction of the energy input that is converted into work output.

## 5. What are the limitations of using T-V diagrams in scientific research?

One limitation of using T-V diagrams is that they are only applicable to ideal gases and do not accurately represent the behavior of real gases. Additionally, T-V diagrams only show the changes in temperature and volume, and do not take into account other variables such as pressure and internal energy.