Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor will none of these. increase. Decrease.d remains same. none of these. increase. Decrease.d remains same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following methods are used to control the speed of DC motors is supply voltage control field current control All of these armature circuit resistance control supply voltage control field current control All of these armature circuit resistance control ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main purpose of providing tertiary winding in a three phase transformer is to suppress harmonic and unbalance in voltage. None of these to carry extra load. to interconnect three voltage systems. to suppress harmonic and unbalance in voltage. None of these to carry extra load. to interconnect three voltage systems. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? Fail to start. It will rotates in normal operation. Either short circuit or open circuit occurs. It will rotates in reverse direction. Fail to start. It will rotates in normal operation. Either short circuit or open circuit occurs. It will rotates in reverse direction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In an induction motor, what is the ratio of rotor input to rotor copper loss? 1/(1-S) 1/S S 1-S 1/(1-S) 1/S S 1-S ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flashing of DC generator means None of these neutralization of residual magnetism. creation of residual magnetism by a DC source. increasing flux density by providing extra ampere-turns in field. None of these neutralization of residual magnetism. creation of residual magnetism by a DC source. increasing flux density by providing extra ampere-turns in field. ANSWER DOWNLOAD EXAMIANS APP