5B10.25-Styrofoam peanuts on Van de Graff generator

5b1025styrofoam_peanuts_on_vdg_gen

Video: Watch this demo

Instructor’s video

Description: This demo shows the buildup of charge on Styrofoam peanuts by the Van de Graff generator.

Equipment:

  • Van de Graff machine
  • Discharge wand
  • Metal can with styrofoam peanuts in it
  • Plastic see through bowl with styrofoam peanuts in it

Setup Procedure:

  1. Connect the Van de Graff to a table that has a three prong cord (grounding prong); else you may get zapped when turning it off.
  2. Fill the metal cup and plastic bowl with styrofoam peanuts. Don’t put too many in the plastic bowl (or they won’t jump out as fast).
  3. With the machine off, set the machine to about half speed.
  4. Connect the discharge wand to the black grounding jack on the machine.

Demonstration Procedure:

  1. Balance the metal can on the top of the dome and turn the machine on.
  2. Note that the peanuts don’t jump out because no charge enters the metal container.
  3. Dischage the dome and take off the metal can.
  4. Balance the plastic bowl on top of the dome and turn the machine on.
  5. Note that the peanuts jump out because charge enters the plastic container and all peanuts gain the same sign charge.
  6. Discharge the machine and turn it off. Remove the plastic bowl and put the peanuts back in the bowl.

Note: This works best with a small layer of peanuts (too many peanuts and they do not jump out as fast).
As with most electrostatic demonstrations, they work best under 50% humidity.

 

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