Ear Piece uses an old-fashioned telephone receiver (the type that had a separate mouthpiece) to demonstrate one way in which electric current can be turned into sound. The visitor walks up to a silent exhibit with the earpiece sticking out of the top. One of many available metal disks or cans is then selected and placed on the earpiece. The metal vibrates from the magnetic fields produced by the current in the earpiece and produces sound. The source of the sound (a transistor radio) is clearly seen through the plastic top of the exhibit.

We'll be adding interesting info and links here. If you have a good one, we need your feedback