Electrical Machines The material used for commutator brushes is mostly carbon. mica. cast iron. copper. carbon. mica. cast iron. copper. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When excitation is increased (over excitation), the synchronous generator operates at leading power factor. lagging power factor. unity power factor. any of the above. leading power factor. lagging power factor. unity power factor. any of the above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The change in speed of a DC generator due to increased load is corrected by increasing input power of the prime mover. increasing terminal voltage. increasing armature resistance. increasing armature cooling. increasing input power of the prime mover. increasing terminal voltage. increasing armature resistance. increasing armature cooling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In Ward-Leonard method of speed control, the direction of rotation of motor is reversed usually reversing the connection of the generator armature terminal. motor armature terminal. motor field terminal. generator field terminal. generator armature terminal. motor armature terminal. motor field terminal. generator field terminal. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 4 pole IM is supplied from a 50 Hz source. Calculate rotor frequency when rotor runs 600 rpm? 30 Hz. Can be determined. 35 Hz. 20 Hz. 30 Hz. Can be determined. 35 Hz. 20 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If Kh is hysteresis constant, f is supply frequency, Bm maximum flux density in core of transformer, the expression of hysteresis loss in transformer, is given by KhfBm3. Khf2Bm1.6. KhfBm1.6. KhfBm. KhfBm3. Khf2Bm1.6. KhfBm1.6. KhfBm. ANSWER DOWNLOAD EXAMIANS APP