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Magnetic Pendulum


Uses electromagnetic induction to make a stationary pendulum oscillate when another is pushed

Description: Demonstrates electromagnetic induction by making a stationary pendulum move when the other is pushed. This happens due to the induced current in the solenoid caused by the constantly changing magnetic field inside of it.

Set up: 1. Make sure the wires on the back are connected with one lead to the back of each of the two solenoids (There are two options: one causes them to swing in unison and the other causes them to swing opposite) 2. Stick approximately a 1.5“ long stack of magnets on the two screw heads on the front of the demo. 3. Make sure that when the pendulums swing the magnets fit through the center without touching the solenoid. 4. Test to see that it works, if it does not make sure that there is a voltage being produced (It should be in the range of .1V - .01V) If it not producing this voltage give a light sanding to the contact surfaces between the pendulum and the copper slits)

Alternate demonstrations: Instead of connecting the two pendulums together, connect one end of the leads to a power source and show that small pulses of current into the solenoid will make it jump around. (WARNING: DO NOT PUT CONSTANT CURRENT IN, JUST PULSES OR YOU WILL BLOW THE SOLENOID AND HAVE TO WIND A NEW ONE BY HAND)

Updated: August 10th, 2015





Needs repair as of Jan 9, 2020: One of the pendula is missing one half of the fulcrum/connector from which it hangs. A metal pin or something similar needs to be soldered on and attached to the loose end of wire.

Demo room information

Location P4
Maker Unknown
Current State Working
demonstrations/5_electricity_and_magnetism/5k_electromagnetic_induction/magnetic_pendulum/start.txt · Last modified: 2020/01/28 18:15 by demoroom