How to Make a Screwdriver Magnet

How to create an electromagnet with some copper wire and a nail.

Step 1: What you'll need: To build the electromagnet described in our Magnets and Electromagnets experiment, you will need:

One iron nail fifteen centimeters (6 in) long

Three meters (10 ft) of 22 gauge insulated, stranded copper wire

One or more D-cell batteries

A pair of wire strippers

Step 2 - Remove some Insulation: Some of the copper wire needs to be exposed so that the battery can make a good electrical connection. Use a pair of wire strippers to remove a few centimeters of insulation from each end of the wire.

Step 3 - Wrap the Wire Around the Nail Neatly wrap the wire around the nail. The more wire you wrap around the nail, the stronger your electromagnet will be. Make certain that you leave enough of the wire unwound so that you can attach the battery. When you wrap the wire around the nail, make certain that you wrap the wire all in one direction. You need to do this because the direction of a magnet field depends on the direction of the electric current creating it. The movement of electric charges creates a magnetic field. If you could see the magnetic field around a wire that has electricity flowing through it, it would look like a series of circles around the wire. If an electric current is flowing directly towards you, the magnetic field created by it circles around the wire in a counter-clockwise direction. If the direction of the electric current is reversed, the magnetic field reverses also and circles the wire in a clockwise direction. If you wrap some of the wire around the nail in one direction and some of the wire in the other direction, the magnetic fields from the different sections fight each other and cancel out, reducing the strength of your magnet.

Step 4 - Connect the Battery Attach one end of the wire to the positive terminal of the battery and the other end of the wire to the negative terminal of the battery. If all has gone well, your electromagnet is now working!

Don't worry about which end of the wire you attach to the positive terminal of the battery and which one you attach to the negative terminal. Your magnet will work just as well either way. What will change is your magnet's polarity. One end of your magnet will be its north pole and the other end will be its south pole. Reversing the way the battery is connected will reverse the poles of your electromagnet.

Tips

• • The more you wrap the wire around the nail the more power it will have.

Warnings

• Take care when working with electronics.
• Magnetic fields can damage TVs and computers.

Things You'll Need

• One iron nail fifteen centimeters (6 in) long
• Three meters (10 ft) of 22 gauge insulated, stranded copper wire
• One or more D-cell batteries
• A pair of wire strippers