Electrical Machines
Commutators in DC machines have a role of which converts

 none of these.
 high voltage DC to low voltage DC.
 Both AC to DC and DC to AC.
 AC to DC.

ANSWER DOWNLOAD EXAMIANS APP

Electrical Machines
What is/are the necessary conditions for voltage build up in self excited generator?

 Poles should contain residual flux.
All of these
 Field winding should be properly connected to armature winding.
 Field winding resistance should be less than critical resistance.

ANSWER DOWNLOAD EXAMIANS APP