A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is 5 Hz 50 Hz 1 Hz 0 Hz TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following motor is more expensive for same KW output rating ? Induction motor. DC Shunt Motor Synchronous motor. AC single phase motor. TRUE ANSWER : ? YOUR ANSWER : ?
Shunt field of DC generators consists of--------number of turns and ---------- conductors respectively large and thick large and thin less and thick less and thin TRUE ANSWER : ? YOUR ANSWER : ?
A DC generator without commutator is a DC generator AC generator DC motor induction motor TRUE ANSWER : ? YOUR ANSWER : ?
A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 4% 5% 25% 2% TRUE ANSWER : ? YOUR ANSWER : ?
How can the synchronous speed of a 3 - Φ IM be varied? By varying number of poles. By varying supply voltage. By varying the supply frequency. Both (A) and (B). TRUE ANSWER : ? YOUR ANSWER : ?
A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 16/9. 9/16. 3/4. 4/3. TRUE ANSWER : ? YOUR ANSWER : ?
Lap winding is prefered for which type of machines? low current and low voltage low current and high voltage high current and low voltage high current and high voltage TRUE ANSWER : ? YOUR ANSWER : ?
Cross magnetization effects which of the following? commutation both 2 and 3 reduction in main field flux reduces the terminal voltage TRUE ANSWER : ? YOUR ANSWER : ?
Essential conditions for two DC generators are connecting for parallel operation is/are rating of generators should be same. both A and B. polarities should be same. terminal voltage should be same. TRUE ANSWER : ? YOUR ANSWER : ?