Electromagnetic Induction
Electromagnetic induction is the generation of a voltage in a conductor that moves relative to a magnetic field or experiences a changing field.
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Electromagnetic induction is the generation of a voltage in a conductor that moves relative to a magnetic field or experiences a changing field.
- Faster movement induces more voltage
- Used in generators
- More coil turns give more voltage
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Electromagnetic Induction?
Within Physics, which covers forces, energy, waves, electricity, magnetism, light and space explained through motion and experiments, this topic explains Electromagnetic Induction. 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 Electromagnetic Induction in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Electromagnetic Induction explains how the physical world behaves, from sport and transport to electricity and medicine.
Electromagnetic Induction in detail
Electromagnetic induction is the production of an e.m.f. in a conductor when the magnetic field through it changes, by moving a magnet in a coil or moving a wire across a field. If the circuit is complete, a current flows.
Faraday's law says the induced e.m.f. is proportional to the rate of change of flux linkage, and Lenz's law says the induced current opposes the change that produces it. A faster movement, a stronger magnet or more turns give a larger e.m.f. Induction is the basis for generators, transformers, induction hobs and wireless charging.
How the interactive helps you understand Electromagnetic Induction
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 Electromagnetic Induction.
Real-life uses and examples
- Predict what a ball, car or circuit will do with Electromagnetic Induction before you do the calculation.
- Explain everyday devices, such as brakes, lifts or chargers, using Electromagnetic Induction.
- Use Electromagnetic Induction to make sense of a practical and its results.
Common mistakes to avoid
- Mixing up Electromagnetic Induction with a related quantity that has different units.
- Forgetting that some quantities, such as force or velocity, also have a direction.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Electromagnetic Induction
What is Electromagnetic Induction?
Electromagnetic induction is the generation of a voltage in a conductor that moves relative to a magnetic field or experiences a changing field.
What are the most important points about Electromagnetic Induction?
The main points are: Faster movement induces more voltage; Used in generators; More coil turns give more voltage.
Why is Electromagnetic Induction useful?
Understanding Electromagnetic Induction explains how the physical world behaves, from sport and transport to electricity and medicine.
How can I practise Electromagnetic Induction?
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 Electromagnetic Induction?
Related topics in Physics include The National Grid, Radioactive Decay, Radiation Safety.