Electrical Machines As compared to an induction motor, the air gap in a DC motor is less than 50%. between 50% and 90%. more. same. less than 50%. between 50% and 90%. more. same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The squirrel cage induction motors are provided with blades in order to balance the rotor dynamically. facilitate cooling of rotor. none of these. eliminate noise. balance the rotor dynamically. facilitate cooling of rotor. none of these. eliminate noise. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following generators negative voltage regulation can occur? over compound generator both B and C series generators shunt generator over compound generator both B and C series generators shunt generator ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 1, 3, 5 1, 4 2, 3 , 5 2, 4 ,5 1, 3, 5 1, 4 2, 3 , 5 2, 4 ,5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The compensating winding in a DC machine is located on pole shoes for avoiding the flashover at the commutator. is located on pole shoes to avoid the sparking at the brushes. is located on commutating poles for improving commutation. is located in armature slots for compensation of the armature reaction. is located on pole shoes for avoiding the flashover at the commutator. is located on pole shoes to avoid the sparking at the brushes. is located on commutating poles for improving commutation. is located in armature slots for compensation of the armature reaction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the effect of armature reaction ? Armature flux weakens the main field flux. Both option B and C. None of the options. Armature flux distorts the main field flux. Armature flux weakens the main field flux. Both option B and C. None of the options. Armature flux distorts the main field flux. ANSWER DOWNLOAD EXAMIANS APP