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Listen to a beam of light! Build a device that converts sound into light and explore the wonders of electromagnetism.
All content in “Electromagnetism”

Turn sound into light and back again

Listen to a beam of light! Learn how to build a simple device in which the signal from a radio is transmitted on a beam of light traveling between a light-emitting diode (LED) and a solar cell. Developed by Exploratorium Teacher Institute staff Don Rathjen and demonstrated by Exploratorium Senior Scientist Paul Doherty.