(a(i))[3]
On Fig. 7.2, sketch a graph to show how the electromotive force (e.m.f.) between terminals X and Y varies with time over two complete revolutions of the coil.
(a(ii))[1]
On Fig. 7.2, mark and label a point P for the e.m.f. when the coil is horizontal, as shown in Fig. 7.1.
(a(iii))[2]
State two ways in which the e.m.f. between terminals X and Y varies.
(b)[3]
State and explain what occurs in the transformer as the student turns the handle of the a.c. generator.
(c)[2]
Explain why power losses in transmission cables are lower when electrical energy is transmitted at higher voltages.