DC Motors In variable speed motor A weaker commutating field is needed at low speed than at high speed A stronger commutating field is needed at low speed than at high speed Same commutating field is needed at low speed than at high speed None of these A weaker commutating field is needed at low speed than at high speed A stronger commutating field is needed at low speed than at high speed Same commutating field is needed at low speed than at high speed None of these ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which method of braking is generally used in elevators? Regenerative braking Plugging None of these Rheostat braking Regenerative braking Plugging None of these Rheostat braking ANSWER DOWNLOAD EXAMIANS APP
DC Motors Excessive sparking at brushes may be caused due to Worn bearings Misaligment of machine Dirt on the commutator Loose coupling Worn bearings Misaligment of machine Dirt on the commutator Loose coupling ANSWER DOWNLOAD EXAMIANS APP
DC Motors When the armature of a D.C. motor rotates, e.m.f. induced is None of these Mutually induced e.m.f. Back e.m.f. Self-induced e.m.f. None of these Mutually induced e.m.f. Back e.m.f. Self-induced e.m.f. ANSWER DOWNLOAD EXAMIANS APP
DC Motors ______ motor has the best speed regulation. Differentially compounded Series Cummulative compounded Shunt Differentially compounded Series Cummulative compounded Shunt ANSWER DOWNLOAD EXAMIANS APP
DC Motors In dc machines fractional pitch winding is used To reduce the sparking To increase the generated emf To improve cooling To reduce the generated emf To reduce the sparking To increase the generated emf To improve cooling To reduce the generated emf ANSWER DOWNLOAD EXAMIANS APP