Calculate these 5 temperatures along this Thermodynamic cycle

AI Thread Summary
The discussion centers on calculating temperatures in a thermodynamic cycle, where T3 is established as four times T1, and T2 equals T1. The user successfully derived T2 as 2T1 but is uncertain about temperatures Ta and Tc. Clarifications are sought regarding the problem's parameters, such as whether it involves ideal gas behavior and the nature of the process (isothermal or adiabatic). It is confirmed that points A and C are on the same isotherm, indicating they share the same temperature. The conversation emphasizes the need for complete problem details to facilitate accurate calculations.
Seeit
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Homework Statement
Calculate the temperatures at places 2, 4, A, B and C if you know:
It's an ideal diatomic gas
T3 = 4T1
T2 = Tb = T4
The axis connecting 1, B and 3 crosses zero.
Relevant Equations
pV = nRT
Laws of thermodynamics
Screenshot_20230325_165532_WPS Office.jpg

I only know T3 = 4•T1
I was able to calculate the T2 = Tb = T4
I built four equations:
T2 = p2V1 / nR
T4 = p1V2 / nR
p1/T1 = p2/T2
V1/T2 = V2/4T1

I put them together and got T2 = 2T1

I can't figure out the temperatures of A and C. I tend to think Ta could equal Tc (then I would be able to calculate it), but I am not sure.
 
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Helo @Seeit ,
:welcome: ##\qquad## !​
Are you sure you have rendered the complete problem statement ? I would expect some more information, like: ideal gas, isothermal (or adiabatic), ...

I also miss an equation of state in your relevant equations (e.g. ##\ pV = NRT##).

Seeit said:
I only know ##T_3 = 4T_1##
How ? Or was that a given ? (In that case it is part of the problem statement)
Same for ##T_2 = T_b = T_4## ?

What about the scale and the axes of the diagram ?

##\ ##
 
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Welcome, @Seeit !

As post #1 has been edited to answer @BvU questions, I suggest considering two things:

-The inverse proportionality between p and V.
-The similarity between polygons 1CBA and 1234 due to the axis connecting 1, B and 3, which makes their corresponding sides proportional.

direct-and-inverse-proportion-1629696427.png
 
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Lnewqban said:
Welcome, @Seeit !

As post #1 has been edited to answer @BvU questions, I suggest considering two things:

-The inverse proportionality between p and V.
-The similarity between polygons 1CBA and 1234 due to the axis connecting 1, B and 3, which makes their corresponding sides proportional.

View attachment 324057
So am I right about thinking that A and C are on the same isotherm and have therefore the same temperature?
 
Seeit said:
So am I right about thinking that A and C are on the same isotherm and have therefore the same temperature?
Correct!
 
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