What change should be made in an AC . generator so that it may become a DC. generator ?
If the slip rings of an AC generator are replaced by a commutator (split rings), then it will become a DC generator.
The essential difference between an AC generator and a DC generator is that :
(a) AC generator has an electromagnet while a DC generator has permanent magnet.
(b) DC generator will generate a higher voltage.
(c) AC generator will generate a higher voltage.
(d) AC generator has slip rings while the DC generator has a commutator.