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Magnetism and Electromagnetism
Quick questions on Electromagnetic induction explained: O-Level Physics
4short Q&A pairs drawn directly from our worked dot-point answer. For full context and worked exam questions, read the parent dot-point page.
What is the transformer?Show answer
A transformer changes the size of an alternating voltage. It has two coils, the primary and the secondary, wound on a soft iron core. An alternating current in the primary produces a changing magnetic field in the core, which induces an alternating voltage in the secondary. The voltages relate to the numbers of turns:
What is q1?Show answer
State what is needed to induce a voltage in a coil. [1 mark]
What is q2?Show answer
A transformer has primary turns and secondary turns, with across the primary. Find the secondary voltage. [2 marks]
What is q3?Show answer
Explain why a transformer does not work with a steady d.c. supply. [2 marks]
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