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P4 Magnetism and magnetic fields

3 dot points across 3 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How does a current make a magnetic field, and how does the motor effect turn a coil?

The magnetic field around a current-carrying wire and a solenoid, electromagnets and what affects their strength, the motor effect, Fleming's left-hand rule, and the electric motor.
A focused answer to OCR Gateway GCSE Physics A topic P4 on electromagnetism, covering the magnetic field around a current-carrying wire and a solenoid, electromagnets and their strength, the motor effect, Fleming's left-hand rule, and how an electric motor works.
9 min answer →

How does a changing magnetic field induce a voltage, and how do generators and transformers use this?

Electromagnetic induction and the generator effect, the factors that affect the induced potential difference, how a generator produces a.c., and how step-up and step-down transformers change the voltage.
A focused answer to OCR Gateway GCSE Physics A topic P4 on electromagnetic induction, covering the generator effect, the factors that affect the induced potential difference, how a generator produces alternating current, and how step-up and step-down transformers change the voltage.
9 min answer →

What is the difference between permanent and induced magnets, and how do we represent magnetic fields?

Permanent and induced magnets, magnetic materials, attraction and repulsion between poles, the magnetic field around a bar magnet and the Earth, and how a compass shows field direction.
A focused answer to OCR Gateway GCSE Physics A topic P4 on magnets, covering permanent and induced magnets, magnetic materials, attraction and repulsion between poles, the magnetic field around a bar magnet and the Earth, and how a compass shows field direction.
8 min answer →