(a)[2]
What is the definition of magnetic flux?
(b(i))[3]
A basic transformer has two coils of wire wound on a soft-iron core, as shown in Fig. 9.1. A sinusoidal current flows in the primary coil. Explain how this current produces an induced electromotive force (e.m.f.) in the secondary coil.
(b(ii))[2]
Explain why the e.m.f. induced in the secondary coil varies.
(c)[2]
Explain why the soft-iron core in part (b) is laminated.