How Do You Build An Electromagnetic Field?
Whether you need to come up with a quick electromagnet to pick up a small piece of metal in a yard or a classroom demonstration, you can create an electromagnetic field by sending an electric current through a metal coil wrapped around an iron core. These fields can temporarily magnetize metal objects by aligning their magnetic domains in one direction, making them act like bar magnets. This can be especially helpful when you need to drive a screw into a hard-to-reach space and can’t risk dropping the screw out of the screwdriver. Strip about a centimeter of the insulation from each end of the copper wire. Wrap the wire around the iron bar in carefully aligned coils. Try not to leave any gaps between the coils, and do not overlap the wire. Make as many coils as the bar will allow without the wire slipping off the ends of the iron bar, and secure the ends with electrical tape. Leave about 5 inches from the end of each wire free to connect to the battery. Attach the ends of the wire to t
