Electrical Machines Two mechanically coupled alternators deliver power at 50 Hz and 60 Hz respectively. The highest speed of the alternators is 3000 rpm. 500 rpm. 600 rpm. 3600 rpm. 3000 rpm. 500 rpm. 600 rpm. 3600 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce mechanical losses. to provide better flux linkage. to reduce hysteresis loss. to reduce eddy current loss. to reduce mechanical losses. to provide better flux linkage. to reduce hysteresis loss. to reduce eddy current loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A large series motor is never started without some mechanical on it because otherwise it will Draw too much current. Develop excessive speed and damage itself. Produce sparking at brushes. Open fuse or circuit breaker. Draw too much current. Develop excessive speed and damage itself. Produce sparking at brushes. Open fuse or circuit breaker. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to reduce copper loss. improve starting torque. improve power factor. improve efficiency. reduce copper loss. improve starting torque. improve power factor. improve efficiency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines CRGO steel is used in the core of transformer to reduce both eddy current and hysteresis loss. ohmic loss. hysteresis loss. eddy current loss. both eddy current and hysteresis loss. ohmic loss. hysteresis loss. eddy current loss. ANSWER DOWNLOAD EXAMIANS APP
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