Electrical Machines A 230 volt dc motor has an armature winding resistance of 0.5 ohm. Calculate the emf induced by the motor if the full load armature current is 23 ampere. 218.5 volt. 220.4 volt. None of these. 120 volt. 218.5 volt. 220.4 volt. None of these. 120 volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direction of the current in the compensating winding is________ to the direction of current in the armature conductors? exactly opposite either of these same None of these exactly opposite either of these same None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slip rings of an induction motors are made of stainless steel. aluminium. phosphor bronze. carbon. stainless steel. aluminium. phosphor bronze. carbon. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 3, 5 1, 2, 6 1, 2, 5 1, 4, 6 1, 3, 5 1, 2, 6 1, 2, 5 1, 4, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 5 KVA transformer has a turns ratio of N1/N2 = 10. The impedance of primary winding is 3+j5 ohms while that of secondary winding is 0.5+j0.8 ohms. The impedance of transformer when referred to primary will be 53+j85 ohms 8+j13 ohms 3.5+j5.8 ohms 3.05+j5.08 ohms 53+j85 ohms 8+j13 ohms 3.5+j5.8 ohms 3.05+j5.08 ohms ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An ideal synchronous motor has no starting torque because rotor is made up of salient poles. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. relative velocity between the stator and rotor mmf’s is zero. rotor is made up of salient poles. relative velocity between stator and rotor mmf’s is not zero. rotor winding is highly reactive. relative velocity between the stator and rotor mmf’s is zero. ANSWER DOWNLOAD EXAMIANS APP