Adding another item on the list of things you probably shouldn’t be trying at home, we got [Brainiac75] giving magnetic levitation a shot using an unmodified induction cooktop and aluminium foil. Although not ferromagnetic, it turns out that aluminium can be made to do interesting things in the magnetic field created by the powerful electromagnet that underlies the induction principle.

Interestingly, although there’s a detection circuit in these units that should detect the presence of an appropriate (ferromagnetic) object, it appears that even a thin sheet of aluminium foil can completely deceive it. The effect is that of a force pushing the foil away from the cooktop’s surface, with foil areas that remain close enough to the ferrite bars on the electromagnet even heating up enough to begin melting the aluminium.

After a bit of fun with various shapes and types of aluminium objects, the video moves on to a scientific explanation of what’s going on. The surface resistivity of the foil is similar enough to ferromagnetic cookware that it fools the sensor, after which the skin effect of aluminium induces a current. This then does the typical Lorentz force things.