Create a working demonstration of Lenz’s law. As the magnet falls down the tube, it demonstrates Lenz’s law. Moving the magnet next to the non-magnetic metal induces an electrical current that generates a magnetic field. This magnetic field overlaps with the magnetic field of the falling magnet. This creates resistance and slows the magnet down.
This system is similar to how electromagnetic brakes work on rollercoasters. The wheel is the tube, and the magnet is attached to the chassis of the train. The movement of the train is slowed without any friction parts to wear out.
- A one foot-long domestic copper plumbing tube
- Strong magnet that fits freely – but closely into the tube
Drop the magnet into the tube.
Watch what happens.