Fiducia TogetherMagnetism and electromagnetism
Magnetic fields, electromagnets, and how a motor works.
Please note: This page explains a word or a process in education. It is general information about the system, the law and the guidance in England — not advice about your child, your school or your exam. If a decision is going against you, get advice from one of the free services we link to before you agree to anything or miss a deadline. If you are revising, check your own exam board's specification: boards word things differently and yours is the one that marks you.
What it is
A magnetic field is the region where a magnetic material or a moving charge experiences a force. A current-carrying wire produces a magnetic field; a solenoid concentrates it.
Where it applies
GCSE physics and combined science.
How it works
The motor effect: a current-carrying wire in a magnetic field experiences a force, given by Fleming's left-hand rule. Reverse the current or the field and the force reverses.
The generator effect is the reverse: moving a conductor in a field induces a potential difference. Transformers use this with alternating current to change voltage.
How to use it in your work
Learn Fleming's left-hand rule with the thumb as motion, first finger field and second finger current — and practise it physically.
Permanent magnets versus induced magnetism, and magnetically hard versus soft materials, are standard distinctions.
For transformers, national grid questions want the reason: high voltage means lower current, so less energy is wasted heating the cables.
Where to get help
Your teacher, your board's specification for the depth required at your tier, and Bitesize for the diagrams.
Revise this with a song
These are ours. We write revision songs because a lot of people remember a tune when they cannot remember a page, and because revising out loud in the kitchen beats staring at a highlighter.
- The Physics Song The GCSE physics specification, set to music.
Where to read more
Last reviewed 2026-08-28 by Fiducia Together · Next review due 2027-08-28
Please note: This page explains a word or a process in education. It is general information about the system, the law and the guidance in England — not advice about your child, your school or your exam. If a decision is going against you, get advice from one of the free services we link to before you agree to anything or miss a deadline. If you are revising, check your own exam board's specification: boards word things differently and yours is the one that marks you.