Theoretically, you could have a permanent magnet and an electromagnet that produce a similar magnetic field. In making an electromagnet, we’re going to consider a coil of wire wrapped around a steel shaft rather than a straight length of wire, but the idea is the same: From the outside, while current is flowing through the coil of wire, the result looks like a magnet. If you read about this history, there’s a lot of talk about current going through a straight length of wire, and how the magnetic field made a compass needle move.
In the earliest days of figuring out electromagnetism, people like André-Marie Ampère and Hans Christian Ørsted learned that a current of electricity running through a wire creates a magnetic field around it. We’ll also briefly mention why this simple example gets to the core of what magnet wire is used for in so many things.Ī permanent magnet and an electromagnet look the same, from a distance. In this article, K&J explores what’s going on. A battery provides an electric current and the nail temporarily becomes a magnet. You might have seen this in elementary school as the classic demonstration of a length of wire wrapped around a nail. Extensionsĭoes changing the number of times you wrap the wire around the nail affect the strength of your electromagnet so that it picks up more paperclips?Ĭan you think of 3 ways to make the electromagnet stronger? (Try altering the number of batteries, the amount of wire, and the type of core you use.K&J Magnetics now offers Magnet Wire! To celebrate the new arrival, we’re using some magnet wire to make a simple electromagnet. Give the magnet plenty of time to cool down between tests. Always conduct this activity with adult supervision. Leaving the magnet on for too long could melt the insulation, causing a burn or fire hazard.
#Electro magnet free#
Leave another 20 cm of wire free at the end. Wrap it neatly around and around the nail, working your way along the nail. Start about 20 cm from one end of your piece of wire.Why do the wires become hot when they’re connected to the battery? What happens when you disconnect the wire? What happens when a wire is coiled around the nail and connected to a battery? Is the nail itself a magnet? Does it matter if it is connected to the battery? Paper clips or other small magnetic objects But be careful! The current flowing through the wire makes the wire hot and drains the battery quickly.Įxplain the relationship between electricity and magnetism. If you leave the wire connected long enough, the nail's magnetic domains will realign enough to make it a permanent magnet. If you disconnect the wire, the magnetic field disappears and the nail is no longer a magnet. But when you coil the wire around an iron nail, the magnetic domains inside the nail line up and make a strong, temporary magnet. The more loops the coil has, the stronger the magnetic field, while the current is flowing.Ī magnet made from just a coil of wire isn't very strong. When you bend the wire into a coil, the magnetic fields around each loop of the coil add up to make a long, thin magnet with north at one end and south at the other. Electrons moving along a wire make a magnetic field that goes in circles around the wire. Moving electrons always create a magnetic field. In this activity, students learn about the relationship between electricity and magnetism by creating and experimenting with their very own electromagnet.Īfter making the magnet, they can explore how it works by making modifications to the number of batteries, the length of wire and number of loops, and the type of core used.Įlectricity and magnetism are linked phenomena.
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