5H30.20 - e/m - Electromagnetic Deflection of Electron Beam - Small

Code Number:
5H30.20
Demo Title:
e/m - Electromagnetic Deflection of Electron Beam - Small
Condition:
Excellent
Principle:
Measure e/m of Electrons
Area of Study:
Electricity & Magnetism
Equipment:
Electron beam deflection tube, 12 V DC power supply, 5 kV DC power supply (2), Helmholtz coils, old black and white or color TV, horseshoe magnets or large neodymium magnets.
Procedure:

Assemble the apparatus as shown and according to the diagrams enclosed. Trying this before class for practice is a very good idea.  The small apparatus which will show only a 90 degree bend at best because of the small diameter of the Helmholtz coils.

References:
  • Michel Glascock, M. Sparlin, "Thomson's e/m Experiment Revisited", AJP, Vol. 40, # 11, Nov. 1972, p. 6631.
  • Ei-18:  Freier and Anderson,  A Demonstration Handbook for Physics.
  • W. Bolton, "The Action of Electric and Magnetic Fields on a Beam of Electrons", Book 4 - Electricity, Physics Experiments and Projects, 1968, p. 45-47.


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