Electrical Machines The mechanical power is developed by a DC motor is maximum when back emf is equal to half of applied voltage. none of above. back emf is equal to twice of applied voltage. back emf is equal to applied voltage. back emf is equal to half of applied voltage. none of above. back emf is equal to twice of applied voltage. back emf is equal to applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 60W 40W 80W 100W 60W 40W 80W 100W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC shunt motor if load is increased, the speed increased slightly. reduce slightly. increase proportional. remains constant. increased slightly. reduce slightly. increase proportional. remains constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 volt dc motor has an armature winding resistance of 0.5 ohm. Calculate the emf induced by the motor if the full load armature current is 23 ampere. 218.5 volt. 220.4 volt. None of these. 120 volt. 218.5 volt. 220.4 volt. None of these. 120 volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then The magnitude will both increase. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. The magnitude will both increase. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following statements are correct ? The leakage reactance of the induction motor should be small. None of these Both 1 and 2. A small value of leakage reactance will increase the maximum power output of motor. The leakage reactance of the induction motor should be small. None of these Both 1 and 2. A small value of leakage reactance will increase the maximum power output of motor. ANSWER DOWNLOAD EXAMIANS APP