- 1). Grasp the solid wire approximately 6 inches from one end. Hold the wire next to the 16-penny nail.
- 2). Wind the wire tightly around the metal nail. Clockwise or counter-clockwise makes no difference. Keep the small winds, or coils, as close as possible to each other. The overall goal is to make a wire coil that runs the entire length of the nail, with no spaces between the winds of the wire.
- 3). Use the wire strippers and remove approximately ¾ of an inch from each end of the wire, exposing the bare copper under the outer insulation.
- 4). Lay the C-cell type battery horizontally on a table. Use a short piece of cellophane tape and secure one end of the coil to one of the battery terminals or ends. Connect the other wire from the coil to the other battery terminal or end. Hold the wires in place with the short pieces of cellophane tape.
- 5). Lay a few small washers on the tabletop. Attempt to pick up the washers using either end of the nail, while the coil is connected to the battery. The nail and coil will act as a small electromagnet. The more winds of coil there are to the outside of the nail, the stronger the electromagnet. Answer this question: Which end of the nail, flat head or pointed, can pick up more washers?
- 6). Place the compass in front of the nail coil electromagnet. Move the tip of the nail around the outside of the compass in a circular fashion. Answer this: Does the needle of the compass follow the direction of the nail?
- 7). Slide the nail from the coil. Answer these questions: Does the wire coil still pickup the washers? Does the wire coil still affect the direction of the compass? One answer will be yes and the other will be no. But which one?
- 8). Wind another coil around one of the ends of a long wooden pencil. Conduct the same experiments as described in Step 5 through Step 7. Answer this question: Does the compass move faster with the smaller coil made with the nail or the larger coil made from the pencil?
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