Having problems with a thermo. cycle

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The discussion revolves around solving a thermodynamic cycle involving isobaric, adiabatic, isothermal, and isochoric processes. The user is struggling with calculating the temperatures at points B and C, consistently arriving at an incorrect value. A suggestion is made that the user may be misapplying the isobaric condition, which should keep the temperature at B equal to that of A. Additionally, it's recommended to verify calculations, ensure unit consistency, and recheck the problem's values for accuracy. The conversation emphasizes the importance of methodical problem-solving and considering alternative approaches.
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Having problems with a thermo. cycle!

OK, so in the problem A->B is isobaric, B->C is adiabatic, C->D is isothermal, D->A is isochoric.

Pa = 2atm, Va = 2 m^3, n = 1mole, Vb = 1/2Va, Pa = 2Pd (That is all the information that is given.)

I always end up with the temperatures of B and C both equaling 2.44x10^4 K. What am I doing wrong?

(After I did all the calculations for A->B, I went over to D since there was no info for C in the problem. After finding the temperature of D, I found the temperature of C since C->D is isothermal. I found the temperature at D by assuming that Va = Vd since it is an isochoric process, and also since Pa=2Pd due to what is given in the problem. So then I used PV=nRT at D to find the temp there.
 
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Then I found the temp of C, since C->D is isothermal. After that, I found the temp of B by using the ideal gas law at B, but it's not working out quite right.) The problem you are having is likely because you are making an incorrect assumption about the process A->B. If this process is isobaric, then the temperature of B should be the same as the temperature of A. Therefore, you should use the temperature of A to calculate the volume of B, and then use the ideal gas law to calculate the temperature of C.
 
Then I went back to C and used the ideal gas law to find the temperature there.)

It seems like you have the right approach in solving this problem. However, there could be a mistake in your calculations or in the values given. It would be helpful if you could provide your calculations or show your work so that we can identify where the error might be. Also, it is important to check your units and make sure they are consistent throughout your calculations. Sometimes, small unit errors can lead to significant differences in the final answer. Additionally, double check the values given in the problem and make sure they are accurate. If you are still having trouble, perhaps try approaching the problem from a different angle or using a different formula to solve for the temperatures. Good luck!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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