Physics Lab - Measurement of Absolute Zero?

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The discussion centers on predicting gas pressure changes at different temperatures using the ideal gas law, with initial conditions set at 20 psi and 20°C. The calculated pressures at 0°C and 100°C are 18.6 psi and 25.5 psi, respectively, which are confirmed as correct by other participants. There is confusion regarding the relevance of "absolute zero" to the problem, as it seems unrelated to the calculations presented. Participants emphasize the importance of showing work in future queries to facilitate assistance. The title of the thread is criticized for being misleading, as it does not reflect the actual content of the discussion.
minidee
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This problem seems straightforward and easy enough, but I still want to check my answers.

Suppose the pressure of the bulb (light bulb I'm guessing used in experiment) is 20 psi (absolute) at 20C. What would you predict the pressure to be at 0C? What would you predict would be at 100C?

I used the ideal gas law equation P = nRT/V and got:
0C Pressure = 18.6 psi
100C Pressure = 25.5 psi

How'd I do? Did I get it right? Big Thanks!
 
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Sorry, I'm missing something, where does "absolute zero" come in?
 
Those answers are correct.

In the future it would be good to show how you calculate your answers ... if they're wrong, we wouldn't be able to help unless we can see your work. :smile:

p.s. whybother makes a good point, the thread title "Measurement of Absolute Zero?" seems unrelated to the question that was asked.
 
That's the headline in the lab manual! I'm not sure why the absolute matters either! Big Thanks for helping! next time i'll include work.
 
minidee said:
That's the headline in the lab manual! I'm not sure why the absolute matters either! Big Thanks for helping! next time i'll include work.

That's the headline in the lab manual? That's horrifying... 0K has nothing to do with this problem... at all...
 
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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