DC Motors In variable speed motor A weaker commutating field is needed at low speed than at high speed Same commutating field is needed at low speed than at high speed A stronger 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 Same commutating field is needed at low speed than at high speed A stronger commutating field is needed at low speed than at high speed None of these ANSWER DOWNLOAD EXAMIANS APP
DC Motors The back emf in a dc motor ______ Aids the applied voltage Opposes the applied voltage None of the listed here Aids the armature current Aids the applied voltage Opposes the applied voltage None of the listed here Aids the armature current ANSWER DOWNLOAD EXAMIANS APP
DC Motors Armature reaction in dc motor is increased When the armature current decreases When the field current increases When the armature current increases By interpoles When the armature current decreases When the field current increases When the armature current increases By interpoles ANSWER DOWNLOAD EXAMIANS APP
DC Motors In which of the following tests only one motor is required? Hopkinson's test Swinburne's test Brake test Field's test Hopkinson's test Swinburne's test Brake test Field's test ANSWER DOWNLOAD EXAMIANS APP
DC Motors The friction and windage losses in a dc motor depends upon Field and armature resistance Flux Speed Armature current Field and armature resistance Flux Speed Armature current ANSWER DOWNLOAD EXAMIANS APP
DC Motors What will happen if the back emf of a dc motor vanishes suddenly? The motor will continue to run The motor will run noisy The armature may burn The motor will stop The motor will continue to run The motor will run noisy The armature may burn The motor will stop ANSWER DOWNLOAD EXAMIANS APP
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