Electrical Machines The torque angle, in a synchronous motor, is the angle between None of these magnetizing electric current and back emf. the rotating stator flux and rotor flux. the supply voltage and the back emf. None of these magnetizing electric current and back emf. the rotating stator flux and rotor flux. the supply voltage and the back emf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The brush-axis of a bipolar dc motor is rotated by 90°. The effect of this rotation on the back emf Eband the torque developed Tdwould be such that both Eb and Td are zero both Eb and Td are unchanged Eb is zero, but Td is unchanged Eb is unchanged, but Td is zero both Eb and Td are zero both Eb and Td are unchanged Eb is zero, but Td is unchanged Eb is unchanged, but Td is zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The following statements relate to compensating winding (CW) and interpole winding (IW) of a dc machine : 1. CW neutralizes the armature reaction under a pole pitch 2. IW is connected in series with armature circuit 3. IW produces mmf in the commutating zone only 4. CWmmf is directed along the brush axis 5. Mmf produced by IW is equal to armature mmf From these, the correct statements are 1, 2, 3, 4 and 5 2, 3, 4 2, 3, 4, 5 1, 3, 4, 5 1, 2, 3, 4 and 5 2, 3, 4 2, 3, 4, 5 1, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Air core transformer as compared to iron core transformer, has no magnetic core loss. more magnetic core loss. less magnetic core loss. more copper loss. no magnetic core loss. more magnetic core loss. less magnetic core loss. more copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field divertor resistance for a DC series motor is of order of 50 Ω 100 Ω 10 Ω 0.1 Ω 50 Ω 100 Ω 10 Ω 0.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which DC motor will have least percentage increase of input current, for the same percentage increase in the torque DC Shunt Motor DC Series Motor Separately Excited DC Motor Compound Wound DC Motor DC Shunt Motor DC Series Motor Separately Excited DC Motor Compound Wound DC Motor ANSWER DOWNLOAD EXAMIANS APP