DC Motors Carbon brushes are preferable to copper brushes because _____ They reduce armature reaction They reduce sparking They have lower resistance They have longer life They reduce armature reaction They reduce sparking They have lower resistance They have longer life ANSWER DOWNLOAD EXAMIANS APP
DC Motors In a dc motor constant torque is produced due to Pole shoes Rotor laminations End plates Commutator Pole shoes Rotor laminations End plates Commutator ANSWER DOWNLOAD EXAMIANS APP
DC Motors The value of back emf in dc motor is maximum at Full load None of the listed here No load Half full load Full load None of the listed here No load Half full load ANSWER DOWNLOAD EXAMIANS APP
DC Motors At the instant of starting when a D.C. motor is put on supply, it behaves like A highly resistive circuit A capacitive circuit A low resistance circuit None of these A highly resistive circuit A capacitive circuit A low resistance circuit None of these ANSWER DOWNLOAD EXAMIANS APP
DC Motors For starting a dc motor a starter is required because It limits the starting current to a safe value It starts the motor It limits the speed of the motor None of the listed here It limits the starting current to a safe value It starts the motor It limits the speed of the motor None of the listed here ANSWER DOWNLOAD EXAMIANS APP
DC Motors If a D.C. shunt motor is working at no load and if shunt field circuit suddenly opens Motor will run at very slow speed Nothing will happen to the motor This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses This will make armature to take heavy current, possibly burning it Motor will run at very slow speed Nothing will happen to the motor This will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses This will make armature to take heavy current, possibly burning it ANSWER DOWNLOAD EXAMIANS APP
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