Electrical Machines In induction motor the 7th harmonic torque may make the motor rotate at (1 / 7)th synchronous speed. This is called cogging. crawling. resonance. harmonics. cogging. crawling. resonance. harmonics. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sequence of induction motor is RYB, then the direction of induction motor can be changed by which of the following sequence? RBY All of these BYR BRY RBY All of these BYR BRY ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. Find the speed of stator magnetic field with respect to rotor? 1470 rpm zero 1500 rpm 30 rpm 1470 rpm zero 1500 rpm 30 rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The supply voltage to an induction motor is reduced by 10%. By what percentage, approximately, will the maximum torque decrease? 10% 40% 19% 5% 10% 40% 19% 5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 1, 2, 5 1, 2, 6 1, 3, 5 1, 4, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer which of the following losses are zero? Copper loss Iron loss Rotational loss All of these Copper loss Iron loss Rotational loss All of these ANSWER DOWNLOAD EXAMIANS APP
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