Demo:

To show this demonstration, the instructor should push down on one side of the lever. This compresses the crystal in the small plastic tube, and an electric current of several thousand volts is created, which jumps the gap between the two pins. When the instructor lifts the lever back to neutral position, another spark will be created from relieving the stress on the crystal.

Explanation:

This demonstration shows the piezoelectric effect, an effect that displays how mechanical energy can be converted to electric energy. When certain materials with a crystalline structure are stressed, they will accumulate an electric charge of very high voltage. The most common materials that display the Piezoelectric effect are quartz, topaz, sugar, and some ceramics. Piezoelectric materials also show an opposite effect; when a strong electric field is applied, a mechanical deformation occurs. This is called the converse piezoelectric effect.

Notes:

• Sometimes when you push down on the lever, a spark is not created. If this happens, make sure you:
  • Push slowly
  • Are pushing down far enough