Is Pressure Directly Proportional to Temperature in Gases?

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Pressure is directly proportional to temperature for a fixed volume of gas, as stated in the lecture notes. The relationship is expressed mathematically as P = P0(1 + αt), where α is approximately 1/273 when using the Celsius scale. This proportionality holds true for ideal gases or under low pressure and moderate temperatures. The value of α is derived experimentally and relates to the concept of absolute zero. The discussion raises questions about the nature of this relationship and the definition of absolute zero.
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My lecturer writes the following in his lecture notes:

" P \propto t for a fixed volume of gas,
P = P0(1+\alphat)

Using the Celcius scale of temperature, we find \alpha \cong 1/273."

Is P really proportional to t?

How do we find \alpha \cong 1/273 using the Celcius temp scale?
 
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hasan_researc said:
My lecturer writes the following in his lecture notes:
" P \propto t for a fixed volume of gas,
Correct

P = P0(1+\alphat)
Just another way of writing the above,

Is P really proportional to t?
Yes - for an ideal gas or at low pressure and reasonable temperatures.

How do we find \alpha \cong 1/273 using the Celcius temp scale?
Experimentally - it's the definition of absolute zero
 
If P \alpha t for a fixed volume of gas, then should P not equal \alpha t, instead of being equal to a constant P-nought times the sum of 1 and \alpha t?
 
mgb_phys said:
Experimentally - it's the definition of absolute zero

How can it be the definition of absolute zero?
 
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