7B20.33 - ESR - Electron Spin

Place the ball without the stem into the apparatus and turn on the magnetic field.  Do not spin the ball.  Switching the direction of the magnetic field also flips the ball 180 degrees.
Precession due to applied magnetic field can also be shown if the ball is spun carefully about a central axis.
Code Number:
7B20.33
Demo Title:
ESR - Electron Spin
Condition:
Excellent
Principle:
Plus and minus 1/2 spin.
Area of Study:
Modern Physics
Equipment:
Teach Spin Apparatus, Standard ball with stem, Special ball without stem.
Procedure:

Place the ball without the stem into the apparatus and turn on the magnetic field.  Do not spin the ball.  Switching the direction of the magnetic field also flips the ball 180 degrees.  Precession due to applied magnetic field can also be shown if the ball is spun carefully about a central axis.  

References:
  • Harold A. Daw, M. Ramona Daw Pomeroy, "The Free Rotator Apparatus", AJP, Vol. 69, # 3, March 2001, p. 289.
  • Malcolm Correll, "Mechanical Analog of Electron or Nuclear Spin Resonance", AJP, Vol. 33, # 4, April 1965, p. 24.
  • Harold A. Daw, "Two Air-Supported Devices for Physics Laboratories and for Physics Demonstrations", AJP, Vol. 33, # 4, April 1965, p. 322.
  • Mark Wilson, "Scanning Tunneling Microscope Measures the Spin-Excitation Spectrum of Atomic-Scale Magnets",  Physics Today, Vol. 59, # 7, July 2006, p. 13.


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