A coil of wire, or solenoid, consists of a wire coiled up into a spiral shape. When an electric current flows, the shape of the magnetic field is very similar to the field of a bar magnet.

A permanent magnet changes the flux through coil, generating a voltage that can be read by an analog voltmeter (you can pretend it's a galvanometer). Connect the voltmeter to the coil or to the DAQ ...

It’s a riot of brass and steel, with a hand crank that drives the main winding shaft while powering a cam that guides the wire along the long axis of the coil form. Cams can be changed out for ...

Note that this magnetic field opposes the original change. For example, if a magnet is moved into a coil of wire, the induced magnetic field tends to repel the magnet back out of the coil.

Since the cook surface uses magnetic ... a homemade induction stove well within reach of anyone with an appropriate power supply and enough wire and inductors to build the coils.