Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is 1 Hz 5 Hz 0 Hz 50 Hz 1 Hz 5 Hz 0 Hz 50 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 4, 6 1, 2, 5 1, 3, 5 1, 2, 6 1, 4, 6 1, 2, 5 1, 3, 5 1, 2, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because rotor is made up of salient poles. rotor winding is highly reactive. relative velocity between the stator and rotor mmf’s is zero. relative velocity between stator and rotor mmf’s is not zero. rotor is made up of salient poles. rotor winding is highly reactive. relative velocity between the stator and rotor mmf’s is zero. relative velocity between stator and rotor mmf’s is not zero. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous generator, if mechanical input is increased with constant excitation, the load angle will decrease None of these increase either increase or decrease decrease None of these increase either increase or decrease ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor speed, in a synchronous machine, becomes more than the synchronous speed during hunting, the damper bars develop induction motor torque. DC motor torque. induction generator torque. synchronous motor torque. induction motor torque. DC motor torque. induction generator torque. synchronous motor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer OC test is conducted on HV side and SC test is conducted on LV side OC test is conducted on LV side and SC test is conducted on HV side both OC and SC tests are conducted on LV side both Oc and SC tests are conducted on HV side OC test is conducted on HV side and SC test is conducted on LV side OC test is conducted on LV side and SC test is conducted on HV side both OC and SC tests are conducted on LV side both Oc and SC tests are conducted on HV side ANSWER DOWNLOAD EXAMIANS APP