Question

Question 11
To convert an AC generator into DC generator

(a) split-ring type commutator must be used
(b) slip rings and brushes must be used
(c) a stronger magnetic field has to be used
(d) a rectangular wire loop has to be used

Answer 1

Option (a) is correct.
To get a direct current (DC, which does not change its direction with time), a split - ring type commutator must be used. With this arrangement, one brush is at all times in contact with the arm moving up in the field, while the other is in contact with the arm moving down. We have seen the working of a split ring commutator in the case of an electric motor. Thus a unidirectional current is produced. The generator is thus called a DC generator.