See when changing magnetic flux linkage induces an emf, use Lenz’s law to predict its direction, and connect a rotating coil to the generator equations.
Learning guide and suggested activities
What this tool shows
Why an emf appears only while magnetic flux linkage is changing
How Lenz’s law makes a coil repel an approaching magnet and attract a retreating magnet
How magnet speed and number of turns affect the relative induced emf
Why rotating-coil flux linkage and induced emf are a quarter-cycle apart
How field strength, turns, area and rotation frequency set peak generator emf
OCR A relevance
OCR A Module 6.3.2: Electromagnetic induction
Faraday’s law, Lenz’s law and magnetic flux linkage
Qualitative induction and rotating-coil generators
AQA relevance
AQA 7408 sections 3.7.5.3 and 3.7.5.4
Magnetic flux and flux linkage
Faraday’s law, Lenz’s law and rotating-coil generators
Try these tasks
Predict whether the coil repels, attracts or has no effect on a moving magnet.
Reverse the magnet pole and motion separately and explain what reverses and what stays the same.
Compare slow and fast motion, then change the number of turns.
Scrub one coil rotation and identify where flux linkage and induced emf are zero or maximum.
Double B, N or f and predict the new peak generator emf.