PASCO TD-8572 HEAT ENGINE_ GAS LAW APPARATUS User Manual
Page 20

Heat Engine/Gas Law Apparatus
012-06014C
16
®
f. Remove the added mass and make any measurements needed to calculate the volume and
pressure of air in the system at point d in the cycle. Show your equations and calculations in
the space below and summarize your results with units.
P
d
=
V
d
=
g. We suspect that transitions from a
➔
b and from c
➔
d are approximately adiabatic. Explain
why.
h. You should have found that the transitions from b
➔
c and from d
➔
a are isobaric. Explain
why this is the case.
Finding Thermodynamic Work from the Diagram
In the next activity you should draw a P- V diagram for your cycle and determine the ther-
modynamic work for your engine.
5.4 Activity: Plotting and Interpreting a
P-V
Diagram
a. Fill in the appropriate numbers on the scale on the graph frame that follows and plot the P-V
diagram for your engine cycle. Alternatively, generate your own graph using a computer
graphing routine and affix the result in the space below.