“A simple electromagnetic sensor to measure current induced by a moving magnetic field!
Move a magnet over a wire and you’ll create an electric current! A very small electric current, but all you need to do to increase the amount of current is add more wire*! One of the simplest ways to do this is to create a coil of wire.
This is the basic phenomenon that enables motors, speakers, and microphones to work! We can also use it as a sensor to measure changes in movement, which is a handy way to build a do-it-yourself seismograph!
For educators, this project is a great way for students to explore, test, and discover the connections between electricity and magnetism.
* More formally speaking: A moving magnetic field causes an electric current to flow through conductive material.
**You can also move the magnet faster and/or get a bigger magnet to increase the amount of current generated.”