DC Motors If a dc motor is comnected across the AC supply it will Run at normal speed Not run Burn due to heat produced in the field winding by eddy currents Run at lower speed Run at normal speed Not run Burn due to heat produced in the field winding by eddy currents Run at lower speed ANSWER DOWNLOAD EXAMIANS APP
DC Motors The rheostatic speed control method is very Unsuitable for rapidly changing loads Suitable for getting speeds above the normal Efficient Economical Unsuitable for rapidly changing loads Suitable for getting speeds above the normal Efficient Economical ANSWER DOWNLOAD EXAMIANS APP
DC Motors In case the conditions for maximum power for a D.C. motor are established, the efficiency of the motor will be 1 Around 90% Less than 50% Anywhere between 75% and 90% 1 Around 90% Less than 50% Anywhere between 75% and 90% 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 The maximum end play of a motor is about 2 mm 6 mm 0.4 mm 10 mm 2 mm 6 mm 0.4 mm 10 mm ANSWER DOWNLOAD EXAMIANS APP
DC Motors In variable speed motor None of these A stronger commutating field is needed at low speed than at high speed 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 None of these A stronger commutating field is needed at low speed than at high speed 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 ANSWER DOWNLOAD EXAMIANS APP
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