Physics 9702 · AS & A Level · Electromagnetic induction

Electromagnetic induction — practice question

(a)[2]

State Faraday’s law that describes electromagnetic induction.

(b)[3]

An ideal transformer is shown in Fig. 10.1. Explain why an alternating current in the primary coil leads to a current in the load resistor.

(c)[3]

In (b), the primary coil has $2700$ turns. The secondary coil has $450$ turns. The e.m.f. $E$ across the primary coil is given by $E = 220\sin(100\pi t)$, where $E$ is in volts and $t$ is measured in seconds. Calculate the root-mean-square (r.m.s.) e.m.f. induced in the secondary coil.

Worked solution & mark scheme

This 8-mark question has a full step-by-step worked solution and mark scheme. One marking point: induced e.m.f. is proportional to the rate of change of magnetic flux linkage

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