5H30.15 - Electrostatic Deflection of Electron Beam

Code Number:
Demo Title:
Electrostatic Deflection of Electron Beam
Electron Beam Deflection by Electrostatic Field
Area of Study:
Electricity & Magnetism
5 kV Power supply (2), Electron beam deflection tube, Helmholtz Coils, 20 V DC Power Supply.

One power supply generates the electron beam. With the other you create an electrostatic potential that bends the beam. After you deflect the electron beam electrostatically you can bend it back to a straight line electromagnetically if desired.

Assembly with the Helmholtz coils is as observed and according to the circuit diagrams.

  • Jonathan Mitschele, "Demonstrating the Sign of a Static Charge Using an Inexpensive Oscilloscope", TPT, Vol. 48, # 6, Sept. 2010, p. 431.
  • Robert Ehrlich, "9.5, Magnetic Field of a Dipole", Why Toast Lands Jelly-Side Down, p. 150.
  • 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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