In this exhibit, we can see the mystery of the rotating pepsi can that act at a distance.
To begin press the bottom "START". Use the aluminum bar to cover 2/3 of the surface of the magnet pole face and observe as the can begins to rotate.
NOW AN EXPLANATION ON HOW THIS WORKS
1- The magnet produces an alternating magnetic field
2- Initially the rising magnetic field from the magnet induces currents in metallic objects (the can and the aluminum bar).
3- These currents generate magnetic fields in the opposite direction so that the objects are repelled.
Next, when the field reaches its maximum value, its rate of change
becomes zero. The induced field becomes also zero .
5- The can becomes quickly demagnetized because it is thin.
6- But the current in the thicker aluminum bar continues longer, so the aluminum bar remains magnetized for a little while.
7- Next the field of the magnet begins decreasing; it induces a field in the opposite direction. The can gets magnetized the new way, but the aluminum bar retains the “old” magnetization and attracts the magnetized can.
8- Voila! rotation begins
You can try changing the position of the aluminum bar
You can also try using other metal sheets from the table.