Magnet Experiment: How to Make an Electromagnet
The discovery that electricity and magnetism are closely related goes as far back as the 1820s, when physicist Hans Christian Oersted demonstrated that an electrical current creates a magnetic field capable of deflecting a compass needle. Oersted’s discovery established that there is more than just one type of magnet.
In fact, you may know from our previous articles that magnets can fall into three categories: permanent, temporary and electromagnet. Theoretically, permanent magnets maintain their magnetism forever while temporary magnets are not really magnets at all but can present magnetic behavior when in the presence of a strong magnetic field. Electromagnets, which we can thank Oersted for, produce magnetism only when in the presence of an electric current.
Electromagnets are present in almost every piece of technology today, so to say they are important could be an understatement. A great way to teach about the importance of electromagnetism and how it occurs is by building your own simple electromagnet. Here’s how:
- Insulated wire
- Take your nail and wire and firmly coil the wire around the nail, leaving two straight pieces of wire at each end.
- Place the battery beside the wire coil and nail.
- Align each end of the wire to the battery. Touch one piece to the negative side and another to the positive.
- Tape the ends of the wire to the battery ends with some tape and wait for a few seconds.
- Test the strength of your electromagnet with a paperclip. You’ll see that the paperclip is attracted to the coiled nail.
To further understand electromagnetism after this magnet experiment, here are some questions to ask:
- Why does the nail have magnetic properties?
- The electric current and the wire produce a magnetic field.
- What happens if the battery is removed?
- The electromagnet is no longer magnetic. Because electromagnets rely on an electric current, once their electric energy source is removed, it turns off.
Now that you’ve created a simple electromagnet, imagine how its properties are used in real-world applications. For instance, many of today’s electronic devices use electromagnets. Examples of the uses include:
- Computer hard drives
- Lifting magnets
- MRI machines
Those are just a few examples, but almost any technology today that uses a motor is powered by electromagnetism. If you want to go a step with your lesson, invite students to create their own inventions using an electromagnet and have a mini science fair where they can showcase their work.