Electrical Machines In an induction motor, what is the ratio of rotor input to rotor copper loss? 1/(1-S) 1-S S 1/S 1/(1-S) 1-S S 1/S ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements: To control the speed of a dc shunt motor above the base speed over a reasonably wide range, the motor must 1. have compensating winding 2. have interpole winding 3. be started using a 3-point starter 4. be started using a 4-point starter Of these statements 1, 2 and 3 are correct 1 and 3 are correct 1, 2 and 4 are correct 2 and 4 are correct 1, 2 and 3 are correct 1 and 3 are correct 1, 2 and 4 are correct 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is/are effects of armature reaction? increase the iron loss increase the maintenance and repair increases the design cost All of these increase the iron loss increase the maintenance and repair increases the design cost All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because there was a break in the armature circuit there was no residual magnetism in the field circuit field winding was wrongly connected field resistance was higher than critical resistance there was a break in the armature circuit there was no residual magnetism in the field circuit field winding was wrongly connected field resistance was higher than critical resistance ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To avoid formation of grooves in the commutator the brushes of same polarity should track each other. brush position has no effect on the commutator grooving. the brushes of opposite polarity should track each other. None of these the brushes of same polarity should track each other. brush position has no effect on the commutator grooving. the brushes of opposite polarity should track each other. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V dc machine has an armature resistance of 1Ω.If the full-load current is 20 A, the differenc in the induced voltages when the machine is running as a motor and as a generator is 40 V 20 V 50 V zero 40 V 20 V 50 V zero ANSWER DOWNLOAD EXAMIANS APP