Electrical Machines The mechanical power is developed by a DC motor is maximum when 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. 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. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single phase transformer has specifications as 250 KVA, 11000 V/415 V, 50 Hz. What are the values of primary and secondary currents? primary = 11.4 A, secondary = 301 A primary = 301 A, secondary = 22.7 A primary = 22.7 A, secondary = 602.4 A primary = 602 A, secondary = 22.7 A primary = 11.4 A, secondary = 301 A primary = 301 A, secondary = 22.7 A primary = 22.7 A, secondary = 602.4 A primary = 602 A, secondary = 22.7 A ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines During hunting of a synchronous motor harmonic are developed in the armature circuit. damper bar develops torque. negative phase sequence currents are generated. field excitation increases. harmonic are developed in the armature circuit. damper bar develops torque. negative phase sequence currents are generated. field excitation increases. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to reduce eddy current loss only. increase the permeability. reduce both eddy current and hysteresis loss. reduce hysteresis loss only. reduce eddy current loss only. increase the permeability. reduce both eddy current and hysteresis loss. reduce hysteresis loss only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Methods of synchronizing of alternator may be done by all dark lamp method. all of these. one dark two bright. all bright lamp method. all dark lamp method. all of these. one dark two bright. all bright lamp method. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sequence of induction motor is RYB, then the direction of induction motor can be changed by which of the following sequence? BYR All of these BRY RBY BYR All of these BRY RBY ANSWER DOWNLOAD EXAMIANS APP