PASCO TD-8565 Adiabatic Gas Law Apparatus - Manual (Page 9)

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Experiment 2B: Work Done by an Isothermal Process
Target Students
General physics, physics for scientists and engineers, physical chemistry, engineering
thermodynamics.
Objectives
To observe that the work performed on a gas is given by
, i.e., the area under a P vs. V curve.
Physical Principles
If the compression occurs isothermally (T remains constant), the Pressure-Volume
relationship is
(2.1b)
and the area under the P vs. V curve becomes,
(2.1b)
V
nRT
P
=
⎟
⎟
⎠
⎞
⎜
⎜
⎝
⎛
= − = ∫
f
i
V
V
V
V
nRT dV
V
nRT W
f
i
ln
1
Procedure
Collect and display data as in Experiment 2A.
dV P W
∫ =
Analysis
A. From the plot of Pressure vs. Volume use the Statistics button (Σ), chose Area and record
the area under the P vs. V curve.
Area = ____________ J