Making a Magnet from a Battery

It is elementary and fun to make a magnet from a battery. Putting a current of electricity through a copper wire produces a magnetic field. As the current flows, the iron core is magnetized, creating an electromagnet.

The current makes a magnetic field that spreads out in widening circles. The magnetic field passes through the coiled wire and the lines of the magnetic field accumulate within the coil. A coiled wire channeling electricity is a solenoid. This is how the magnetic field is created. The nail used for the magnet has miniscule magnetic fields in it. They line up in a single direction because of the effect of the magnetic field in the coil.

This magnet works with electricity, which means it isn't a permanent magnet. The power of the magnet is increased or decreased by the strength of the current running through it. Energy escapes as heat when the electric current runs through the copper wire. An increase in current produces more heat. Be careful when increasing the current as the heat increases exponentially.

Supplies

A few plain materials will suffice for this project.

• 3 to 6-inch iron nail
• 1 foot single strand copper wire
• D-cell or lantern battery
• wire strippers
• masking tape
• wire cutters

The wire has to be insulated to work. Braided or rubber coated wire will work for this project, but the enamel coated wire in a single strand is the best choice. You can use a 9-volt battery, but it won't continue to generate the current as long as the D-cell or lantern battery. A knife will strip the wire, but wire strippers are more efficient and safer to use.

Step 1 – Strip

Strip away about an inch of the insulation from each end of the wire. Exposing the wire ensures a good connection to the battery terminals.

Step 2 – Tape

Attach one end of the nail to the wire using masking tape. A few inches of the wire needs to hang off of the nail at each end.

Step 3 – Wrap

Tightly wrap the copper wire around the the iron nail from one end to the opposite end. More wire secured around the nail makes the magnet perform better. Each wrap of the wire should touch the prior wrap. The wrapping should be in a single direction, so two magnetic fields aren't created, as they negate each other. This lessens the power of the electro magnet because the two fields struggle.

Step 4 – Tape Again

Tape this end of the copper wire to the nail.

Step 5 – Attach to Battery

Affix one exposed end of the copper wire to the positive terminal and touch the other to the negative terminal. The electro magnet should now be working. Which end of the wire is affixed to the negative and positive terminals doesn't affect performance of the magnet. Changing the wire ends around changes the polarity, as one is the south and one is the north pole of the magnet.

Now try to lift up some paper clips, iron filings or little pieces of thin wire.