Electrical Machines The output voltage of a DC generator is E = V + IaRa. E = V + Ra. E = V – IaRa. E = V + Ia. E = V + IaRa. E = V + Ra. E = V – IaRa. E = V + Ia. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 2, 3 1, 3 1, 4 2, 4 2, 3 1, 3 1, 4 2, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following induction motor has the highest starting torque? Slip ring induction motor. Squirrel cage induction motor. None of these Same in both induction motors. Slip ring induction motor. Squirrel cage induction motor. None of these Same in both induction motors. 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, 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 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 4 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What are the starters used for starting of cage motors? All of these. Star-delta starter. Auto transformer starter. DOL starter. All of these. Star-delta starter. Auto transformer starter. DOL starter. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starter is not used with large DC motor for starting, it will provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. ANSWER DOWNLOAD EXAMIANS APP
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