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Electromagnetism
Charge! That’s what this area of physics is all about (well, electrical charge and its motion, to be exact). Explore electricity, magnetism, and electromagnetic fields—and harness the power to transform sound into light.
All content in “Electromagnetism”

Electromagnetism Introduction

Explore the interactions between electricity and magnetism.

Turning Light into Sound

Can you listen to a beam of light? Audio signals can be transmitted along radio waves through space, and in electrical pulses through wires. Visible light and other forms of electromagnetic radiation can carry audio signals, too. In this activity, learn how to build a simple device in which the signal from a radio is transmitted along a beam of light traveling between a light-emitting diode (LED) and a solar cell. This science snack was developed by Exploratorium Teacher Institute staff Don Rathjen and demonstrated by Exploratorium Senior Scientist Paul Doherty.