An a.c. generator is arranged with its coil of wire perpendicular to the magnetic field. The coil of wire is then turned slowly to produce an alternating electromotive force (e.m.f.). As the coil rotates, a graph of induced e.m.f. against time is drawn. Which part of the graph shows a rotation of three-quarters of a turn?
- AOP
- BOQ
- COR
- DOS