Electrical Machines In a loaded DC motor, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Speed of DC motor can be controlled by varying all of these. resistance of armature culture. applied voltage. its flux oer pole. all of these. resistance of armature culture. applied voltage. its flux oer pole. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The 3 - Φ induction motors are, by a very considerable margin, the most widely used AC motors as they have maximum efficiency and maximum starting torque. these are cheaper in cost, simple and rugged in construction. they have very good speed regulation. they are capable of operation under range of leading and lagging pf. they have maximum efficiency and maximum starting torque. these are cheaper in cost, simple and rugged in construction. they have very good speed regulation. they are capable of operation under range of leading and lagging pf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator with a diameter of 50 cm rotating at 1000 rpm. For a brush width of 1.5 cm, find the time of commutation in ms. 0.443. 0.512. 0.649. 0.573. 0.443. 0.512. 0.649. 0.573. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-φ alternator has negligible stator resistance. A short circuit test is conducted on this alternator. At a particular speed, a field current of If1 is required to drive the rated armature current. If the speed of the alternator is reduced to half, the field current required to maintain rated armature current Cannot be predicted due to insufficient data. Would be equal to If1/2. Would be equal to If1. Woud be equal to 2If1. Cannot be predicted due to insufficient data. Would be equal to If1/2. Would be equal to If1. Woud be equal to 2If1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature flux is.............with respect to main field flux or main field poles? stationary rotates opposite direction None of these rotates same direction stationary rotates opposite direction None of these rotates same direction ANSWER DOWNLOAD EXAMIANS APP