DC Motors The direction of rotation of a D.C. series motor can be changed by Interchanging field terminals Either of (A) and (B) above None of these Interchanging supply terminals Interchanging field terminals Either of (A) and (B) above None of these Interchanging supply terminals ANSWER DOWNLOAD EXAMIANS APP
DC Motors If the speed of a dc shunt motor is increased the back emf of the motor will Remains same Increase Become zero Decrease Remains same Increase Become zero Decrease ANSWER DOWNLOAD EXAMIANS APP
DC Motors Which D.C. motor is generally preferred for cranes and hoists? Series motor Differentially compounded motor Cumulatively compounded motor Shunt motor Series motor Differentially compounded motor Cumulatively compounded motor Shunt motor ANSWER DOWNLOAD EXAMIANS APP
DC Motors One D.C. motor drives another D.C. motor. The second D.C. motor when excited and driven Runs as a generator Does not run as a generator None of these Also runs as a motor comes to stop after sometime Runs as a generator Does not run as a generator None of these Also runs as a motor comes to stop after sometime ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens Motor will come to stop This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses Nothing will happen to motor This will make armature to take heavy current, possibly burning it Motor will come to stop This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses Nothing will happen to motor This will make armature to take heavy current, possibly burning it ANSWER DOWNLOAD EXAMIANS APP
DC Motors Carbon brushes are preferable to copper brushes because _____ They have longer life They reduce sparking They reduce armature reaction They have lower resistance They have longer life They reduce sparking They reduce armature reaction They have lower resistance ANSWER DOWNLOAD EXAMIANS APP
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