Work to compress a gas (constant external pressure)

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The work done to compress a gas under constant external pressure is calculated using the equation w = -P(ext)delta(V). This equation applies to both gas expansion and compression, with the sign of delta(V) changing based on the process. When comparing two gases compressed to the same volume but at different external pressures, the work done will differ, with higher pressure resulting in greater work. The discussion highlights that while the work is indeed a factor of the external pressure, the rate of compression also varies, affecting the dynamics of the process. Ultimately, understanding the relationship between pressure and work is crucial in thermodynamics.
1drdan
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What is the work to compress a gas under constant external pressure?
It seems that it is supposed to be w = -P(ext)delta(V)
This equation is certainly true for expansion of a gas, is it also true for compression?
So if we have two gases, same initial conditions, same delta(v) under compression. One is compressed by 10 atm and the other by 5 atm. They end at the same volume, but have different work done on them?
The observational difference I can see is that the 10 atm compression would occur faster than the 5 atm compression. Is the work really a factor of 2 different?
Or, is work really dependent upon the lower of internal and external pressures, and the books talk about expansion more than compression?
 
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Yes, it's the same concept, only the sign of delta(V) changes depending on the situation.
 

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