External pressure on a piston with/without friction

AI Thread Summary
The discussion revolves around the effects of external pressure on a piston in a gas cylinder, considering both friction and the work done during compression and expansion. The relationship between pressure, force, and area is established with the equations P = F/A and W = P*Delta(V). It is noted that work is proportional to F*Delta(V), and the presence of friction affects the energy in the system regardless of the piston’s movement direction. The challenge lies in accurately sketching the graphs of the external force ratio F/A as a function of volume V during the gas's compression and expansion. The conversation highlights the need for clarity on whether the problem requires a focus on work or graphing.
Dishsoap
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Homework Statement



"A gas is enclosed in a cylinder with a piston of area A. The relation between the pressure and volume of the gas at a constant temperature T is shown in Figure B. On a similar figure, sketch graphs of the ratio of the external force F to the area A, F/A, as a function of V, as the gas is (1) is slowly compressed, and (2) is slowly expanded at the temperature T. Ther is a force of sliding friction f between the piston and the cylinder.

The image is similar to
Ideal_gas_isotherms.png



Homework Equations



P = F/A
W = P*Delta(V)

The Attempt at a Solution



All I did was say that the work is proportional to F*Delta(V). I think that the work would be the same in both cases, since the work done by friction would remove remove energy from the system regardless of which direction the piston is moving. From there, I don't know how to draw the graph.
 
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Read the problem text again. Does it ask the work?

ehild
 

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