Electrical Machines If the frequency of input voltage of a transformer is increased keeping the magnitude of voltage unchanged, then Pe will increase but Ph will decrease Ph will decrease but Pe will remain same Ph will increase but Pe will decrease both hysteresis loss(Ph) and eddy current loss(Pe) will increase Pe will increase but Ph will decrease Ph will decrease but Pe will remain same Ph will increase but Pe will decrease both hysteresis loss(Ph) and eddy current loss(Pe) will increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The introduction of interpoles in between the main poles improves the performance of a dc machine, because the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque the inequality of air-gap flux on the top and bottom halves of the armature is removed the flux waveform is improved with reduction in harmonics a counter-emf is induced in the coil undergoing commutation the interpoles produce additional flux to augment the developed torque ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A triangular mmf wave is produced in the air gap of an electric machine. Such wave is produced by stator of a dc machine. stator of a induction machine. rotor of a dc machine. rotor of an synchronous machine. stator of a dc machine. stator of a induction machine. rotor of a dc machine. rotor of an synchronous machine. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of IM the torque is inversely proportional to slip. directly proportional to slip2. inversely proportional to √slip. directly proportional to slip. inversely proportional to slip. directly proportional to slip2. inversely proportional to √slip. directly proportional to slip. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following methods are suitable for the speed control of squirrel cage induction motor? 1. Voltage control. 2. Frequency control. 3. Pole changing method. 4. Rotor resistance control select the correct answer using the codes given below:- 1, 3 and 4. 1, 2 and 3. 2, 3 and 4. 2 and 4. 1, 3 and 4. 1, 2 and 3. 2, 3 and 4. 2 and 4. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For the speed control of polyphase squirrel cage induction motor, if frequency of operation is decreased with constant V, Tst increases None of these constant supply voltage V, starting torque Tst decreases either of these constant V, Tst increases None of these constant supply voltage V, starting torque Tst decreases either of these ANSWER DOWNLOAD EXAMIANS APP