Electromagnet Experiment

Build your own electromagnet!  For this experiment you will need the following:

 
  1. A large iron nail (about 3 inches)
  2. About 3 feet of thin coated copper wire
  3. A fresh D-size battery
  4. Some paper clips

Directions

  1. Wrap the wire around the nail leaving about 8 inches of loose wire at each end.  Try not to overlap the wires.
  2. Remove about an inch of the plastic coating from both ends of the wire.
  3. Attach one end of the wire to one end of a battery.
  4. Attach the other end of the wire to the other end of the battery. (Taping the wires to the battery works best.  But be careful—the wire could get very hot!)

Now Try This

  1. Put the point of the nail near a few paper clips and it should pick them up!
  2. How many paper clips can you pick up with the electromagnet?
  3. What other object will it pick up?

Why it Works

A battery produces electrons.  Looking at a battery, you can see that one end is marked plus (+) and the other is marked minus (-). Electrons collect at the negative end of the battery and will flow to the positive end if you let them. You can let the electrons flow from one end to the other through a wire.  If you attach a wire directly between the positive and negative sides of a battery, a couple things will happen:

  1. Electrons will flow from the negative side of the battery to the positive side as fast as they can.
  2. A small magnetic field is generated in the wire. This is why it will attract metal objects.