This how it works covers How Electric Current Creates a Magnetic Field within Magnetic Fields for GCSE Physics. Revise Magnetic Fields in Magnetism for GCSE Physics with 14 exam-style questions and 12 flashcards. Use this page as part of a wider topic revision path rather than treating it as an isolated fact. It is section 6 of 13 in this topic. Use this how it works to connect the idea to the wider topic before moving on to questions and flashcards.
⚙️ How Electric Current Creates a Magnetic Field
Any moving electric charge creates a magnetic field around it. When current flows through a wire, the moving electrons create circular magnetic field lines around the wire.
- Straight wire: Field lines are concentric circles around the wire. Use the right-hand grip rule — wrap your right hand around the wire with thumb pointing in current direction; your fingers curl in the direction of field lines.
- Coil (solenoid): The circular fields from each turn add together, creating a uniform field inside the coil that resembles a bar magnet — with a north and south pole at each end.
- Iron core: Soft iron inside the coil becomes an induced magnet, massively amplifying the total magnetic field strength.
This connection between electricity and magnetism (electromagnetism) is one of the most powerful ideas in physics — it underpins motors, generators, transformers, and wireless communication.
Practice questions for Magnetic Fields
What happens when two like magnetic poles (e.g. north and north) are brought close together?
State the rules for the attraction and repulsion of magnetic poles.