Physics 9702 · AS & A Level · Electromagnetic induction
Electromagnetic induction — practice question
A coil of insulated wire is wrapped around a copper core, as shown in Fig. 10.1. An alternating current flows through the coil. The heating effect produced by the current in the coil is negligible.
(a)[4]
Explain why the temperature of the core increases.
(b)[5]
Two hollow tubes of the same length are suspended vertically as shown in Fig. 10.2. One tube is plastic and the other is aluminium. Two small similar bar magnets A and B are positioned above the tubes and then released together. The magnets do not strike the tube sides. Explain why magnet B takes much longer than magnet A to fall through the tube.
Worked solution & mark scheme
This 9-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Magnetic flux in the core is changing and non-uniform” …