Which of the following motor is more expensive for same KW output rating ? AC single phase motor. Synchronous motor. Induction motor. DC Shunt Motor TRUE ANSWER : ? YOUR ANSWER : ?
What is the emf generated by a 4 pole Lap connected DC Motor rotating at 1500 rpm having 1000 conductors and useful flux per pole is 0.4 mWb. 30 volts. 40 volts. 20 volts. 10 volts. TRUE ANSWER : ? YOUR ANSWER : ?
Which one of the following statement is correct ? In an induction motor if the air gap is increased then its speed will increase its efficiency will improve its power factor will reduce its speed will reduce TRUE ANSWER : ? YOUR ANSWER : ?
Slip test is performed to determine All of these positive sequence reactance and negative sequence reactance slip direct axis reactance and quadrature axis reactance TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following induction motor has the highest starting torque? Squirrel cage induction motor. Same in both induction motors. None of these Slip ring induction motor. TRUE ANSWER : ? YOUR ANSWER : ?
In DC machine torque depends on which of the following? both A and B speed armature current (I) flux (φ) TRUE ANSWER : ? YOUR ANSWER : ?
If the field circuit of a DC shunt motor is opened The armature current will reduce. DC Shunt Motor The motor will attain dangerously high speed. The speed of motor will be reduced. TRUE ANSWER : ? YOUR ANSWER : ?
Due to magnetic saturation, the flux per pole in a DC machine without brush shift increases in generators but decreases in motor with load. decreases in both generators and the motors with load. increases in both the generators and the motors with load. decreases in generators and increases in motor with load. TRUE ANSWER : ? YOUR ANSWER : ?
The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 1, 4 2, 3 1, 3 TRUE ANSWER : ? YOUR ANSWER : ?
In DC series motor the speed is ______________ proportional to the armature current. directly. inversely. has no relation. none of these. TRUE ANSWER : ? YOUR ANSWER : ?