Electrical Machines In a loaded DC generator, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with fall of terminal voltage. deteriorate with rise in terminal voltage. improve with fall of terminal voltage. improve with rise in terminal voltage. deteriorate with fall of terminal voltage. deteriorate with rise in terminal voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the armature electric current is increased to double its previous value, and the time of commutation is halved, how will the reactance voltage vary? It will be doubled. It will remain the same. It will becomes four times. It will be halved. It will be doubled. It will remain the same. It will becomes four times. It will be halved. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/60. PN/3000. PN/2. PN/120. PN/60. PN/3000. PN/2. PN/120. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The synchronous speed of an induction motor will be increased by increasing of frequency. increasing number of poles. decreasing of frequency. speed can not be increased. increasing of frequency. increasing number of poles. decreasing of frequency. speed can not be increased. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Under which of the following conditions is a dc motor provided with compensating winding used ? 1. Wide range of speed control above normal 2. Wide range of steady load variation with no speed control 3.Wide range of rapid variation in load Select the correct answer using the codes given below : Codes : 2 and 3 1 and 2 1, 2 and 3 1 and 3 2 and 3 1 and 2 1, 2 and 3 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following is done in speed control of DC motor by field flux control? Inserting an additional resistance in the field circuit. Inserting an additional resistance in the armature circuit. Any of above. Inserting resistance to armature circuit and field circuit. Inserting an additional resistance in the field circuit. Inserting an additional resistance in the armature circuit. Any of above. Inserting resistance to armature circuit and field circuit. ANSWER DOWNLOAD EXAMIANS APP