Experiment #1

• Put all the items you need to build your electromagnet on a table. You need a few feet of AWG 14 wire, a long steel nail (3 or 4 inches is fine) and a 9-volt battery. Put a few paper clips on the table and a permanent magnet, if you have one. Put the end of the nail near the paper clips; nothing happens, as the nail and the paper clip are not magnetized. Put the nail near the permanent magnet and the nail is drawn to it. Rub the nail along one end of the magnet several times in the same direction. Put the nail near the paper clip and the clip moves toward the nail because the nail has been slightly magnetized.
  
  

Experiment #2

• Strip about ½ inch of plastic off the end of the wire so the metal is visible. Wind the wire around the nail starting at the top. Leave a few inches of wire loose, as you need to connect it to the battery. Continue winding around the nail tightly until you get to the bottom of the nail. Strip the other end of the wire, and attach the ends of the wire to the battery terminals. Move the nail toward the paper clip. The clip moves toward the nail and sticks to it because you have created a magnetic force using electrical current from the battery. Try putting your nail near a heavier metal object. Feel the force as the nail is attracted to the object. It's not likely to be very great, because you have only wound wire around the nail once.
  
  

Experiment #3

• Repeat the previous experiment, but this time use a longer piece of wire so that you can wind from the bottom to the top of the nail, then back down to the bottom, and finally back to the top. You now have three layers of wire wrapped around the nail. Strip the ends of the wires and attach them to the battery. Move the nail toward the paper clip. You'll find the paper clip move toward the nail much sooner than before. Put the nail near the other metal object. The magnetic force is much greater than last time. This is because the extra wire wound around the nail has made the electromagnet more powerful.
  
  

Experiment #4

• Keep your nail connected to the battery. Move the tip of the nail near one end of the permanent magnet. The nail is either pulled toward the magnet or pushed away, depending on whether the pole on the end of the nail is the same as or different from the pole on the magnet (north or south pole). Repeat the experiment by putting the nail near the other end of the magnet. Whatever happened before, the opposite should occur this time. Remove the wires from the battery terminals and swap them so that the wire that was on the "+" terminal is now on the "-" terminal and vice versa. Put the nail near the same end of the magnet as before and you'll find the opposite reaction. This is because you have altered the flow of electricity through the wire, which changes the magnetic poles.