The diagram shows the basic structure of a transformer.
(a) Explain how a transformer works.
(b) A transformer is used to change the 230 volt mains electricity supply to the 12 volts needed to operate a low voltage halogen lamp. The current through the halogen lamp is 4 amps.
Calculate the current drawn by the transformer from the mains electricity supply.
Assume that the transformer is 100% efficient.
Write down the equation you use, and then show clearly how you work out your answer.
Current = .................. amps
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From Q9 P3 AQA Specimen Paper (Higher)