A power adapter for a smart speaker contains a transformer with a primary coil and a secondary coil.
The potential difference across the primary coil = 240 V.
The potential difference across the secondary coil = 9.0 V.
The current in the secondary coil is 1.6 A.
Calculate the current in the primary coil.
Use the equation:
current in primary=potential difference across secondary×current in secondarypotential difference across primary \text{current in primary} = \frac{\text{potential difference across secondary} \times \text{current in secondary}}{\text{potential difference across primary}} current in primary=potential difference across primarypotential difference across secondary×current in secondary28 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.