Suggest way/s in an a.c. generator to produce a higher e.m.f.
Each one of the following changes will increase emf (or voltage) in a simple generator except :
(a) increasing the number of turns in the armature coil
(b) winding the coil on a soft iron armature
(c) increasing the size of the gap in which the armature turns
(d) increasing the speed of rotation
State two ways to produce a higher e.m.f. in an a.c. generator.