Teaching Minds-On Experiments on Electromagnetism in Secondary Schools

Falling piece of magnet/metal in tube of copper with/without slit(s)

Lenz Current Tubes (two types) – dropping neodymium magnet down in 0.5 meter long, copper tube, causes a slow fall of the magnet. The moving magnetic field creates a strong opposing magnetic field, due to eddy currents in the cylindric conductor. The fall takes about 20 seconds in our set-up.
Cutting the tube in a special way (©GK), the fall is fast – demonstrating that direction of eddy currents is perpendicular to the direction of the magnet movement. The fall takes only about 12 seconds.