The relationship between electricity and magnetism enables electric current to create magnetic fields, which can be used to attract magnetic objects. Unlike permanent magnets, electromagnets can be turned on and off to release the objects they have attracted. Although industrial uses of electromagnets is more complex in design and structure, the fundamental structure involved remains the same as electric current is passed through a metal to create a flow of electrons. Simple electromagnets can be easily created from everyday household items.
Try adding more batteries to the circuit to make the electromagnet more powerful.
If the coils of wire overlap on the nail the current won't be as strong as magnetic fields are working against each other instead of in one direction. The ends of the stripped wire will get very hot so take care not to touch them.
Wrap the copper wire very tightly around the nail. Form about 50 coils and make sure that they do not overlap at any point. Leave about 8 inches of coil free at either end of the nail.
Strip about an inch of the plastic coating from both ends of the wire using the wire strippers.
Connect one end of the wire to the negative terminal of the battery. Use tape to hold the wire down.
Open the switch and connect the wire from the other end of the nail to the terminal on the switch.
Cut a short piece of wire and tape one end of it to the positive terminal of the battery.
Attach the other end of the wire from the positive terminal of the battery to the other terminal on the switch.
Close the switch to let the current flow through the circuit. Move the end of the nail towards some paper clips and it should pick them up.
- magnet image by Dave from Fotolia.com