605. How can you make an electromagnet from a battery and copper wire?
You'll need a large steel nail or bolt, too. Wrap about 100 turns of copper wire around the nail, keeping the turns fairly uniformly spaced. Make sure that both ends of the wire coil, start and finish, project out from the windings. When you're done winding the coil, strip off about 1 cm of the insulation from each end of the wire. Now connect one end of the wire to the positive terminal of a AA alkaline battery and the other end of the wire to the negative terminal of that battery. The nail will become a strong magnet and will be able to pick up other nails or paper clips with ease. Electricity will also heat the wire, so be prepared for the electromagnet to become uncomfortably hot. Detach the wires from the battery when you're no longer able to hold everything safely.