In contrast to Crookes’ radiometer, which rotates due to electromagnetic radiation, the analogous acoustic radiometer demonstrates radiation pressure. The apparatus consists of two panes attached to opposite ends of a horizontal arm that is pivoted at its center. One side of either pane is acoustically reflective and the other absorptive. The apparatus rotates when placed in an enclosure of high-intensity acoustic noise. Experimental values of the terminal angular velocity are in reasonable agreement with approximate theoretical predictions based on radiation pressure.
REFERENCES
1.
Arthur E.
Woodruff
, “The Radiometer and how it does not work
,” Phys. Teach.
6
, 358
–363
(1968
), and references therein.See also
Frank S.
Crawford
, “Running Crooke’s radiometer backwards
,” Am. J. Phys.
54
, 490
(1986
);R. E.
Bell
, “The reversing radiometer
,” Am. J. Phys.
51
, 584
(1983
);S. L.
Paveri-Fontana
, “An elementary model for the radiometer
,” Am. J. Phys.
45
, 447
–450
(1977
), and references therein.2.
Timothy G. Simmons, Bruce Denardo, Andrés Larraza, and Robert Keolian, “Acoustic Radiometer Demonstration,” Proc. of the 16th International Congress on Acoustics and 135th Meeting of Acoustical Society of America, 1998, Vol. I, edited by Patricia Kuhl and Lawrence Crum, pp. 129–130.
3.
Andrés
Larraza
, “A demonstration apparatus for an acoustic analog to the Casimir effect
,” Am. J. Phys.
67
, 1028
–1030
(1999
);Andrés
Larraza
and Bruce
Denardo
, “An acoustic Casimir effect
,” Phys. Lett. A
248
, 151
–155
(1998
);Andrés
Larraza
, Christopher D.
Holmes
, Robert T.
Susbilla
, and Bruce
Denardo
, “The force between two parallel rigid plates due to the radiation pressure of broadband noise: An acoustic Casimir effect
,” J. Acoust. Soc. Am.
103
, 2267
–2272
(1998
).4.
T. G. Wang and C. P. Lee, “Radiation Pressure and Acoustic Levitation,” in Nonlinear Acoustics, edited by Mark F. Hamilton and David T. Blackstock (Academic, San Diego, 1998), Chap. 6.
5.
Seth J.
Putterman
, “Sonoluminescence: Sound into Light
,” Sci. Am.
272
(2
), 46
–51
(Feb. 1995
);Lawrence A.
Crum
, “Sonoluminescence
,” Phys. Today
47
(9
), 22
–29
(Sep. 1994
).6.
Small Parts, Inc., Miami Lakes, FL (800-220-4242, www.smallparts.com). Part numbers: Y-NVC-500AOF (noise-absorbing foam), Y-VJ-1244 (synthetic sapphire vee jewel bearing), and Y-VJPX-7D (stainless steel vee jewel pivot).
7.
Paul Lorrain, Dale R. Corson, and François Lorrain, Electromagnetic Fields and Waves, 3rd ed. (Freeman, New York, 1987), pp. 599–602.
8.
L. D. Landau and E. M. Lifshitz, Fluid Mechanics, 2nd ed. (Butterworth-Heinemann, Oxford, 1987), pp. 255–260. See also Ref. 4.
9.
Frank M. White, Fluid Mechanics, 4th ed. (McGraw–Hill, New York, 1999), pp. 24–25, 453, 457–458.
This content is only available via PDF.
© 2004 American Association of Physics Teachers.
2004
American Association of Physics Teachers
AAPT members receive access to the American Journal of Physics and The Physics Teacher as a member benefit. To learn more about this member benefit and becoming an AAPT member, visit the Joining AAPT page.