In this paper we demonstrate that the observed discrepancy between the measured and expected values of the heat capacity ratio for air obtained using the PASCO Adiabatic Gas Law Apparatus1 is due primarily to the finite compression time in the experiment. We devised an empirical method for obtaining a more accurate value of γ using this apparatus, which should be adaptable to other methods of measuring γ that use approximately adiabatic processes.
REFERENCES
1.
Adiabatic Gas Law Apparatus, Model TD-8565, PASCO scientific, 10101 Foothills Blvd., Roseville, CA 95747; http://www.pasco.com.
2.
William W.
McNairy
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The LabPro interface and Logger Pro software are produced by Vernier Software and Technology, 13979 SW Millikan Way, Beaverton, OR 97005-2886; http://www.vernier.com.
4.
Instruction Manual and Experiment Guide for the PASCO scientific Model TD-8565 Adiabatic Gas Law Apparatus (PASCO scientific, 1994), p.9.
5.
No significant changes in these results were obtained when the data were fit to higher order polynomials.
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D. G.
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C. G.
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(Sept. 1992
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J. L.
Hunt
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O. L.
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2004
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