Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2, 3 and 4 1, 3 1, 2 and 3 3 only 1, 2, 3 and 4 1, 3 1, 2 and 3 3 only ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 30 W. 25 W. 28 W. 36 W. 30 W. 25 W. 28 W. 36 W. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by s2. f / s. sf. sf / 2. s2. f / s. sf. sf / 2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following motor is preferred for belt conveyor? Slip ring induction motor. Synchronous motors. Universal motor. Reluctance motor. Slip ring induction motor. Synchronous motors. Universal motor. Reluctance motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The fall in speed of the DC generator due to increase in load can be corrected by cooling the armature. increasing the input to the prime mover. increasing the excitation. reducing the load voltage. cooling the armature. increasing the input to the prime mover. increasing the excitation. reducing the load voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 volt dc series motor having an armature resistance of 0.2 Ω takes a load current of 60 A. What will be the torque produced at the shaft of the motor? Consider brush drop of 1V. can not be determined. 133.22 N-m 234.76 N-m. 266.20 N-m. can not be determined. 133.22 N-m 234.76 N-m. 266.20 N-m. ANSWER DOWNLOAD EXAMIANS APP
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