The primary coil of an electric toothbrush charger transformer is connected to a 240 V mains supply.
The potential difference across the secondary coil is 12 V.
The primary coil has 800 turns.
Calculate the number of turns on the secondary coil.
28 exam-style questions on Edexcel GCSE Physics 13.2 Transformers and the National Grid. Each one has a worked solution and a mark scheme showing where the marks go.