3B22.51 - Standing Pulses in a Spring

Code Number:
Demo Title:
Standing Pulses in a Spring
Wave Motion
Area of Study:
Acoustics, E & M
Spring, Mechanical Oscillator, Oscillator Amplifier, and Wave Generator.

Attach the spring to the mechanical oscillator and stretch to between 30 and 60 cm.  Turn the wave generator from 10 to 70 Hz.  As you sweep that set of frequencies you should observe the number of  standing pulses in the spring go from 2 to about 7.

When using the camera to image the spring you will need to put a white screen behind the spring.

  • Theodore Foster, Willem van Wyngaarden, Arthur Cary, and John Mottmann, "On the g/2 Acceleration of a Pulse in a Vertical Chain", TPT, Vol. 51, #7, Oct. 2013, p. 394.
  • Casey Rutherford, "A Fresh Look at Longitudinal Standing Waves on a Spring", TPT, Vol. 51, #1, Jan. 2013, p. 22.
  • P. J. Ouseph and Thomas Poothackanal, "Longitudinal and Transverse Waves in a Spring", TPT, Vol. 32, #5, May 1994, p. 285.
  • P. J. Ouseph, "Standing Longitudinal Waves", AJP, Vol. 55, #7, July 1987, p. 666.
  • A. D. Bulman, "A Standing-Wave Apparatus", Model-Making for Physics, p. 53.
  • Robert Ehrlich, "J.9. Longitudinal Waves Around a Circle", Turning the World Inside Out and 174 Other Simple Physics Demonstrations, p. 135.

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