Electrical Machines The power factor of an induction motor operating at no load will have a value around unity 0.2 lead 0.9 lag 0.2 lag unity 0.2 lead 0.9 lag 0.2 lag ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods of speed control is not affected through stator side? Change of rotor resistance. Change of number of pole. Change of supply voltage. Change of supply frequency. Change of rotor resistance. Change of number of pole. Change of supply voltage. Change of supply frequency. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The short circuit test on a transformer is conducted to obtain hysteresis loss. core loses only. copper losses. eddy current loss. hysteresis loss. core loses only. copper losses. eddy current loss. 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 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 2, 3 , 5 1, 3, 5 2, 4 ,5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If we increase the rotor reactance value, the maximum torque will increase not changed decrease None of these increase not changed decrease None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the mechanical power is developed by a DC motor maximum Back emf is equal to half of applied voltage. back emf is equal to applied voltage. Back emf is equal. None of above. Back emf is equal to half of applied voltage. back emf is equal to applied voltage. Back emf is equal. None of above. ANSWER DOWNLOAD EXAMIANS APP