5H30.15-Bending an Electron Beam

5h3015bending_an_electron_beam_2 5h3015bending_an_electron_beam

Video: Watch this demo

Instructor’s video

Description: This demonstration shows that a magnetic field can deflect a beam of moving electrons.


  • Crooke’s Tube
  • High voltage DC power supply
  • Bar magnet
  • 2 Banana plug cables
  • 2 Alligator clips
  • Electric Magnetizer

Setup Procedure:

  1. Using the electric magnetizer, magnetize two bar magnets.
  2. Connect the Crooke’s tube to the high voltage DC power supply.
  3. Test to make sure it works correctly.
  4. Face the appropriate side of the crooke’s tube to the class.

Demonstration Procedure:

  1. Turn on the power supply.
  2. Bring a bar magnet near the tube to deflect the beam.
  3. If you reverse the magnet and use the other pole, note that the beam moves in the opposite direction.
  4. When finished, turn off the power supply.

High Voltage
High voltages are produced. Never touch when the power supply is on.

X-ray radiation
This device emits X-ray radiation. Avoid long exposure.