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keemosabi
Jan19-09, 11:22 AM
1. The problem statement, all variables and given/known data
The pressure and volume of a gas are changed along a path ABCA in the figure. The vertical divisions on the graph represent 2.5 multiplied by 105 Pa, and the horizontal divisions represent 1.5 multiplied by 10-3 m3. Determine the work done (including algebraic sign) in each segment of the path.
http://www.webassign.net/CJ/cj6_p15-10alt.gif


(c) C to A
J

3. The attempt at a solution
Isn't it just the area under the curve from C to A? Area of a trapezoid? 5625 J?

Andrew Mason
Jan19-09, 11:25 AM
3. The attempt at a solution
Isn't it just the area under the curve from C to A? Area of a trapezoid? 5625 J?Not quite. Is work being done by the gas or on the gas? What does this do to the sign of the area/work?

AM

keemosabi
Jan19-09, 11:30 AM
Not quite. Is work being done by the gas or on the gas? What does this do to the sign of the area/work?

AM
Ahh. I see. Since the volume is decreasing the work done by the gas is negative.

Thank you for the help.