In a DC machine the armature mmf is rotating with respect to field poles. stationary with respect to armature. rotating with respect to field poles as well as armature. stationary with respect to field poles. TRUE ANSWER : ? YOUR ANSWER : ?
The effect of ------------------ on main field flux is armature reaction? armature flux armature current All of these armature mmf TRUE ANSWER : ? YOUR ANSWER : ?
When the mechanical power is developed by a DC motor maximum Back emf is equal. back emf is equal to applied voltage. Back emf is equal to half of applied voltage. None of above. TRUE ANSWER : ? YOUR ANSWER : ?
If the applied voltage to a dc machine is 230 V, then the back emf, for maximum power developed, is 230 V 460 V 115 V 200 V TRUE ANSWER : ? YOUR ANSWER : ?
A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm and rotor input power is 2KW. Find the rotor copper loss? 80W 100W 60W 40W TRUE ANSWER : ? YOUR ANSWER : ?
Voltage regulation of transformer is given by (E2 - V2) / V2 (V2 - E2) / V2 (V2 - E2) / E2 (E2 - V2) / E2 TRUE ANSWER : ? YOUR ANSWER : ?
The flux is maximum in the following part of a DC motor: under leading pole tip. under the interpole. pole core. under trailing pole tip. TRUE ANSWER : ? YOUR ANSWER : ?
For a given torque, reducing diverter resistance of a DC series motor causes increase in speed but armature currnet remains the same. decrease in speed but armature current remains the same. decrease in speed demanding less armature current. increase in speed demanding more armature current. TRUE ANSWER : ? YOUR ANSWER : ?
In a resistance split phase motor, what is the range of torque angle? 70° to 85° 25° to 30° 90° 0° TRUE ANSWER : ? YOUR ANSWER : ?
In case of a compensated DC series motor, the compensating winding is provided As a separate unit. In parallel with the armature winding. In parallel with the field winding. In series with the armature winding. TRUE ANSWER : ? YOUR ANSWER : ?