5D30.30 Glowing Pickle


Atomic excitation and emission


The variac is connected to the pickle and a large voltage is applied. The pickle begins to sizzle and steam. After a short time, the pickle glows. 



  • [1] Pickle
  • [1] Plate
  • [2] Copper wire
  • [1] Power cord with 2 alligator clips
  • [1] Variac
  • (Optional) Handheld spectroscopes
  • (Optional) Camera

Classroom Assembly

  1. Place a pickle on the plate.
  2. Wrap one wire around the pickle. Spear the other wire through the middle of the pickle.
  3. Attach the alligator clips to each fork.
  4. Plug the power cord with alligator clips into the variac.

Important Notes

  • The voltage used in this demonstration is potentially lethal! Perform this demonstration with extreme caution!
  • The pickle glows at one electrode only.
  • This demonstration smells strongly. Do not allow the pickle to glow for a long period of time in a small lecture room.
  • The light from the pickle can be seen in large lecture halls, but not the details of the setup unless there is a camera. Camera recommended.


  1. Plug in the variac.
  2. Turn on the variac.
  3. Increase the variac voltage to about 120 V.
  4. Hold your microphone near the pickle (taking extreme care not to touch it!) to demonstrate that the pickle is sizzling.
  5. Wait for the pickle to glow. Let it glow for a few moments before turning off the variac.
  6. (Optional) The sodium D line can be seen fairly clearly using a handheld spectroscope. Spectroscopes can be distributed in a small class.


Additional Resources



  • Don't attempt this at home!

Last revised

  • 2020


  • Original construction: the plug with alligator clips was made from a standard 2' long power cord. Each lead of the cord was soldered to an alligator clip. All other equipment was purchased.

Related AV

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If you have any questions about the demos or notes you would like to add to this page, contact Ricky Chu at ricky_chu AT sfu DOT ca.