Electrical Machines If the load current and flux of a DC motor are held constant and voltage applied across it armature is increased by 5%, the speed of the motor will Reduce by 5%. Increase by 5%. Depends on other factor. Remain unchanged. Reduce by 5%. Increase by 5%. Depends on other factor. Remain unchanged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Wave winding is prefered for which of the following rating? high current and low voltage high current and high voltage low current and high voltage low current and low voltage high current and low voltage high current and high voltage low current and high voltage low current and low voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called crawling. harmonics. resonance. cogging. crawling. harmonics. resonance. cogging. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main purpose of providing tertiary winding in a three phase transformer is None of these to interconnect three voltage systems. to carry extra load. to suppress harmonic and unbalance in voltage. None of these to interconnect three voltage systems. to carry extra load. to suppress harmonic and unbalance in voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by None of these Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). None of these Ns = 120f /p × ( 1 - r). Ns = 120f / p × ( 1 - s ). Nr = 120f / p × (1-s). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generators, the cause of rapid brush wear may be any of above. rough commutator surface. severe sparking. imperfect contact. any of above. rough commutator surface. severe sparking. imperfect contact. ANSWER DOWNLOAD EXAMIANS APP