Induced Currents

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Description:

Demo 1: A 3200 turn coil is connected to two LEDS connected in anti-parallel polarity. When a cylindrical magnet is quickly inserted into the coil one LED with light. When the magnet is pulled out of the coil, the other LED will light, Flip the magnet around, and it will change which LED lights as the magnet is inserted and taken out of the coil.

Demo 2: A large coil and a bipolar Red Green LED is mounted on a piece of plywood, There is also a strong magnet attached to the board. When the magnet is quickly inserted into the coil the LED will flash Green or red, When the magnet is pulled out of the coil, the other color LED will light, Flip the magnet around, and it will change which LED lights as the magnet is inserted and taken out of the coil.

Demo 3 A linear motor salvaged from an old hard drive is the heart of this demo.A small bulb is attached to the leads of the coil and it will light when the coil is moved up and down on the string magnet. Attaching an oscilloscope to the leads shows the direct relation between induced EMF and changing flux -- both sign and how the magnitude. relates to the speed of the movement. Attach a battery to the leads and the coil will climb out of its holder.

Location:

• Shelf J-2 and 4