Electrical Machines In a transformer operating at constant voltage if the input frequency increases, the core loss decrease. increase. None of these remains constant. decrease. increase. None of these remains constant. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be 250 V. zero. about 100 V. very small, say about 2 or 3 V. 250 V. zero. about 100 V. very small, say about 2 or 3 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The oscillation in a synchronous motor can be damped out by maintaining constant excitation. providing damper bars in the rotor pole faces. oscillation cannot be damped. running the motor on leading power factors. maintaining constant excitation. providing damper bars in the rotor pole faces. oscillation cannot be damped. running the motor on leading power factors. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Series generators are used in which of the following applications? Air crafts. Used as boosters in dc distribution or transmission. Arc welding. All of these Air crafts. Used as boosters in dc distribution or transmission. Arc welding. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The polarity of a DC generator can be reversed by increasing field current. reversing field electric current as well as direction of rotation. reversing the field current. any of above. increasing field current. reversing field electric current as well as direction of rotation. reversing the field current. any of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The current drawn by the a 230 V DC motor of armature resistance 0.5 Ω and back emf 200 V is 600 60 40 660 600 60 40 660 ANSWER DOWNLOAD EXAMIANS APP
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