Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 1, 2, 3 2, 3, 4 2, 3 ,5 2, 3, 4, 5 1, 2, 3 2, 3, 4 2, 3 ,5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor has negative speed regulation? Shunt motor Cumulative compound motors Differential compound motor Series motor Shunt motor Cumulative compound motors Differential compound motor Series motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the necessity of copper brushes in a dc motors? To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. To absorb the mechanical shocks produced during running condition. To convert alternating supply current to direct current. To increase the flux cutting by the rotor. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM has a rotor speed of 987 rpm find rotor frequency? 0.70 Hz. 0.75 Hz. 0.65 Hz. 60 Hz. 0.70 Hz. 0.75 Hz. 0.65 Hz. 60 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 3/4. 9/16. 16/9. 4/3. 3/4. 9/16. 16/9. 4/3. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In field flux method speed control of DC Motor is constant power drive above base speed. constant torque drive above the base speed. constant hp drive below the base speed. constant torque drive below the base speed. constant power drive above base speed. constant torque drive above the base speed. constant hp drive below the base speed. constant torque drive below the base speed. ANSWER DOWNLOAD EXAMIANS APP