7D30.70 Cyclotron

Description: This demonstration mimics the motion of a particle in a real magnetic cyclotron.

Equipment:

  1. Cyclotron model
  2. Wimhurst Machine
  3. Cables
  4. Metallic balls(ping pong balls wrapped with aluminum tape/foil)

Procedure:

  1. Attach opposite terminals of the Wimhurst machine to the continuous metallic strip and the non continuous strips.
  2. Place conducting ball inside of the model.
  3. Set up camera such that the whole class can observe.
  4. Begin cranking the Wimhurst machine to provide a potential difference to the strips.
  5. Watch as the ball is accelerates around the bowl, mirroring the effects a magnetic cyclotron.

Concept: Like a real cyclotron, the “particle” is accelerated by the electric field but instead of an alternating current, this is done by a direct current. Due to the opposite charges of the strips, it provides an “alternating” effect as the ball swirls around the bowl. In addition, instead of a magnetic field causing the centripetal force, in the model, it is provided by the normal force of the bowl.

Tips:

  1. Remember to discharge the equipment before touching any metal parts!!!!!
  2. If the ball remains stationary, give it a nudge to get it going and the model will do the rest.