Electrical Machines An ideal synchronous motor has no starting torque because relative velocity between the stator and rotor mmf’s is zero. rotor is made up of salient poles. rotor winding is highly reactive. relative velocity between stator and rotor mmf’s is not zero. relative velocity between the stator and rotor mmf’s is zero. rotor is made up of salient poles. rotor winding is highly reactive. relative velocity between stator and rotor mmf’s is not zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In circle diagram for induction motor, diameter of circle represents which of the following ? Line voltage. Rotor current. Running torque. Slip. Line voltage. Rotor current. Running torque. Slip. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 1, 2, 5 2, 4, 5, 6 3, 4, 5 2, 3, 6 1, 2, 5 2, 4, 5, 6 3, 4, 5 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature MMF waveform of a DC machine is rectangular. triangular. pulsating. sinusoidal. rectangular. triangular. pulsating. sinusoidal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For P pole machine relation between electrical degrees and mechanical degrees is θelec = P/2*θmech θelec = 2/P*θmech θelec = θmech θelec = 4/P*θmech θelec = P/2*θmech θelec = 2/P*θmech θelec = θmech θelec = 4/P*θmech ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which motors are preferred for refrigeration and air conditioning in smaller units? Reluctance motors. Universal motors. Induction motors. Stepper motors. Reluctance motors. Universal motors. Induction motors. Stepper motors. ANSWER DOWNLOAD EXAMIANS APP
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