Electrical Machines The frequency of voltage generated by an alternator having 8 poles and rotating at 250 rpm is 60 Hz. 16.67 Hz. 25 Hz. 50 Hz. 60 Hz. 16.67 Hz. 25 Hz. 50 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of rotation of a 3 - Φ induction motor can be reversed by disconnecting any one phase. transposing all the three leads from the supply. transposing any two leads from slip rings. transposing any two leads from supply. disconnecting any one phase. transposing all the three leads from the supply. transposing any two leads from slip rings. transposing any two leads from supply. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The maximum power developed in cylindrical synchronous machine is occurs at a load angle of 0o. Greater than 90o. 90o. less than 90o. 0o. Greater than 90o. 90o. less than 90o. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage to a dc machine is 230 V, then the back emf, for maximum power developed, is 460 V 230 V 115 V 200 V 460 V 230 V 115 V 200 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor speed of an induction motor is given by Ns = 120f / p × ( 1 - s ). Ns = 120f /p × ( 1 - r). None of these Nr = 120f / p × (1-s). Ns = 120f / p × ( 1 - s ). Ns = 120f /p × ( 1 - r). None of these Nr = 120f / p × (1-s). ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature of DC machine is made of silicon steel lamination to reduce hysteresis loss only. increase the permeability. reduce eddy current loss only. reduce both eddy current and hysteresis loss. reduce hysteresis loss only. increase the permeability. reduce eddy current loss only. reduce both eddy current and hysteresis loss. ANSWER DOWNLOAD EXAMIANS APP
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