Advance Preparation
and Setup

The sandpaper is for sanding the insulation off the ends of this magnet wire. The three insulated pieces of bell wire are for connecting the coil to the galvanometer in Step 8 and also for connecting the batteries together in series in Step 12 (if you have battery holders). To cut the bell wire to size, or to remove insulation from the ends, students would need the wire strippers. Having a few available for the class should suffice.

Students measure the induced current with a galvanometer. It is placed in series with the circuit containing the current to be measured, so all the current in the circuit flows through the galvanometer. The galvanometer is not a voltmeter. If it were hooked up to a battery, the current through the galvanometer would be enormous, limited only by the resistance in the hookup wire. The result would be a blown meter or at least a blown fuse.