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 2, 3 ,5 2, 3, 4 1, 2, 3 2, 3, 4, 5 2, 3 ,5 2, 3, 4 1, 2, 3 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM is running at a full load speed of 980 rpm. If it delivers an air gap power of 98000 Watt, calculate the rotor ohmic loss? 1960 Watt. 1800 Watt. 980 Watt. 1920 Watt. 1960 Watt. 1800 Watt. 980 Watt. 1920 Watt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the armature current of 5 Amp is flowing through the dc motor the torque produced is 47 Nm. Keeping the speed constant if the armature current is increased to 7 amp, calculate the new torque. Assume losses to be constant. 38.5 Nm. 74 Nm. 65.8 Nm. 27.73 Nm . 38.5 Nm. 74 Nm. 65.8 Nm. 27.73 Nm . ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole DC generator runs at 750 rpm and generate an emf of 240 V. The armature is wave wound and has 792 conductors. If the total flux from each pole is 0.0145 Wb. What is the leakage co-efficient? 1.2. 1.4. 1.8. 1.5. 1.2. 1.4. 1.8. 1.5. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The primary and secondary windings of a transformer are electrically linked. conductively linked. inductively linked. mechanically linked. electrically linked. conductively linked. inductively linked. mechanically linked. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature mmf of a DC machine has stepped distribution and rotates at the speed of armature. triangular space distribution and is stationary in space. trapezoidal space distribution and is stationary in space. triangular space distribution and rotates at the speed of armature. stepped distribution and rotates at the speed of armature. triangular space distribution and is stationary in space. trapezoidal space distribution and is stationary in space. triangular space distribution and rotates at the speed of armature. ANSWER DOWNLOAD EXAMIANS APP