Electrical Machines The armature reaction mmf in a DC machines has a form of trapezoidal. rectangular. triangular. sinusoidal. trapezoidal. rectangular. triangular. sinusoidal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines With the increase in speed of DC motor Both back emf as well as line current increase. Back emf increase but line current falls. Back emf falls and line current increase. Both back emf as well as line current fall. Both back emf as well as line current increase. Back emf increase but line current falls. Back emf falls and line current increase. Both back emf as well as line current fall. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has the highest power factor at full load? Capacitor run Capacitor start Shaded pole Resistance split phase Capacitor run Capacitor start Shaded pole Resistance split phase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Synchronising power of a synchronous motor varies inversely as 1/Xs directly as synchronous reactances Xs directly as Xs2 All of these inversely as 1/Xs directly as synchronous reactances Xs directly as Xs2 All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The air gap between the yoke and armature is dc machine is kept very small to avoid locking of the armature. All of these to achieve a stronger magnetic field. to avoid over heating. to avoid locking of the armature. All of these to achieve a stronger magnetic field. to avoid over heating. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For the purpose of starting an induction motor, star/delta switch is an equivalent to auto transformer of ratio 57.7% 33.3% 66.3% 50% 57.7% 33.3% 66.3% 50% ANSWER DOWNLOAD EXAMIANS APP
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