Electromagnets
An electromagnet is a coil of wire that becomes a magnet when a current flows through it, and it can be switched on and off.
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An electromagnet is a coil of wire that becomes a magnet when a current flows through it, and it can be switched on and off.
- A soft iron core strengthens it
- More turns or current make it stronger
- Used in cranes and doorbells
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Electromagnets?
Within Physics, which covers forces, energy, waves, electricity, magnetism, light and space explained through motion and experiments, this topic explains Electromagnets. Physics topics explain how things move, push, heat up and carry energy, so each one here pairs a definition with a live model you can change.
Check that you can explain Electromagnets in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Electromagnets explains how the physical world behaves, from sport and transport to electricity and medicine.
Electromagnets in detail
An electromagnet is a coil of wire that becomes a magnet when current flows. A current-carrying wire produces a magnetic field in circles around it, and winding it into a solenoid concentrates the field, giving one like a bar magnet. An iron core greatly strengthens it.
The strength increases with more turns, a larger current and an iron core. Unlike permanent magnets, electromagnets can be switched on and off, which makes them useful in scrapyard cranes, relays, doorbells, loudspeakers and maglev trains. Reversing the current reverses the poles.
How the interactive helps you understand Electromagnets
Watch the magnetic field in the interactive. Use any sliders or buttons it offers to change the values and see how the magnetic field responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Electromagnets.
Real-life uses and examples
- Explain everyday devices, such as brakes, lifts or chargers, using Electromagnets.
- Use Electromagnets to make sense of a practical and its results.
- Answer “explain” questions by linking Electromagnets to a clear cause and effect.
Common mistakes to avoid
- Forgetting that some quantities, such as force or velocity, also have a direction.
- Mixing up Electromagnets with a related quantity that has different units.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Electromagnets
What is Electromagnets?
An electromagnet is a coil of wire that becomes a magnet when a current flows through it, and it can be switched on and off.
What are the most important points about Electromagnets?
The main points are: A soft iron core strengthens it; More turns or current make it stronger; Used in cranes and doorbells.
Why is Electromagnets useful?
Understanding Electromagnets explains how the physical world behaves, from sport and transport to electricity and medicine.
How can I practise Electromagnets?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Electromagnets?
Related topics in Physics include Generators and Dynamos, Atomic Structure, Half-Life.