Electrical Machines The material used for commutator brushes is mostly carbon. mica. copper. cast iron. carbon. mica. copper. cast iron. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines At what power factor, the voltage regulation of a transformer can be zero ? Zero power factor. Lagging power factor. Unity power factor. Leading power factor. Zero power factor. Lagging power factor. Unity power factor. Leading power factor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An IM cannot run at synchronous speed because induction motor will become synchronous motor. air friction will prevent it. rotor torque will not be produced. none of above. induction motor will become synchronous motor. air friction will prevent it. rotor torque will not be produced. none of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 250 V DC generator in run at rated speed with no excitation. The open circuit voltage will be zero. 250 V. very small, say about 2 or 3 V. about 100 V. zero. 250 V. very small, say about 2 or 3 V. about 100 V. 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 becomes four times. It will remain the same. It will be doubled. It will be halved. It will becomes four times. It will remain the same. It will be doubled. It will be halved. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator the actual flux distribution depends upon shape of the pole shoe. size of air gap. all of above. clearance between tips of the adjacent pole shoes. shape of the pole shoe. size of air gap. all of above. clearance between tips of the adjacent pole shoes. ANSWER DOWNLOAD EXAMIANS APP