Electrical Machines A 220 V DC generator is run at full speed without any excitation. The open circuit voltage will be 220 V. zero. about 2 V. about 50 V. 220 V. zero. about 2 V. about 50 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following motors DC excitation is not required? hysteresis motor reluctance motor 3-phase synchronous generator 3-phase synchronous motor hysteresis motor reluctance motor 3-phase synchronous generator 3-phase synchronous motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To control the speed of an induction motor, the supply frequency is reduced by 10%. For the same magnetizing current to remain constant, the supply voltage must be increased by 20% reduced by 20% reduced by 10% increased by 10% increased by 20% reduced by 20% reduced by 10% increased by 10% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the air gap of IM is increased, ____________ will increase. power factor. speed. air gap flux. magnetizing current. power factor. speed. air gap flux. magnetizing current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For satisfactory performance of 3-phase 480V, 60 Hz induction motor, the supply voltage at 50 Hz should be equal to 420 V. 350 V. 480 V. 400 V. 420 V. 350 V. 480 V. 400 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mechanical power is developed by a DC motor is maximum when back emf is equal to half of applied voltage. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. none of above. back emf is equal to half of applied voltage. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. none of above. ANSWER DOWNLOAD EXAMIANS APP