Thermodynamics - compression of a gas in a piston-cylinder device

AI Thread Summary
The discussion revolves around the compression of an ideal gas in a piston-cylinder device, starting at 100 kPa and 300 K with an initial volume of 5 liters. The gas is compressed according to the relationship pV^2=constant until it reaches a final temperature of 400 K. A participant incorrectly assumes that the work done is zero due to the freely moving piston, suggesting a horizontal line on the p-V diagram. However, this assumption is challenged, emphasizing the need to consider work in relation to pressure and volume changes. The conversation highlights the importance of accurately applying thermodynamic principles to determine work in such processes.
roldy
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Homework Statement



An ideal gas initially at 100kPa and 300K is contained in a piston-cylinder device with an initial volume of 5 liters. The gas is then compressed slowly according to the relationship that pV^2=constant until a final temperature of 400K is reached. Sketch the process on a p-V diagram and find how much work is done in this process.

Homework Equations


pV^2=costant


The Attempt at a Solution



I'm not sure in my logic but since this is a freely moving piston-cylinder device, the work should be 0 which would result in a horizonatal line. Is this assumption correct?
 
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No. Review the definition of work as it pertains to pressure and volume changes.
 
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