Question

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

Answer 1

increasing the size of the gap in which the armature turns
The increase in the size of the gap, in which armature turns, has no effect on voltage.