A student is investigating an emergency hand-cranked generator, which operates as an alternator to produce electrical energy. The simplified diagram below shows the internal coil of the alternator, which is connected via slip rings to a resistor, RRR, forming a complete circuit:
The hand-crank is used to rotate the coil at a constant speed. Explain how this rotation induces an alternating current in the circuit containing the resistor.
Describe the shape of a graph that shows how the potential difference across the resistor varies with time for exactly two complete rotations of the hand-crank.
When the circuit is broken by disconnecting the resistor RRR, the user notices that the hand-crank suddenly becomes much easier to turn. Explain why.
Induced potential, transformers and the National Grid (physics only) (HT only) Questions
Practise AQA GCSE Physics Induced potential, transformers and the National Grid (physics only) (HT only) with exam-style questions for Foundation and Higher tier. 15 questions covering Induced potential (HT only), Uses of the generator effect (HT only), Microphones (HT only), and Transformers (HT only), matched to the AQA GCSE Physics (8463) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.