Electrical Machines Short circuiting is caused in the armature winding due to failure of insulation between two commutator bars. grounding of two or more turns of the same coil. any of above. failure of insulation between two turns of coil. failure of insulation between two commutator bars. grounding of two or more turns of the same coil. any of above. failure of insulation between two turns of coil. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For pure resistive load what is the armature reaction? magnetization demagnetization All of these cross magnetization magnetization demagnetization All of these cross magnetization ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines No load test of 3-phase induction motor gives which of the following? None of these constant loss both A and B variable loss None of these constant loss both A and B variable loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The rotor of a three phase induction motor has an impedance of 0.4 + j4 ohm per phase at standstill the maximum torque occurs at a slip of _____________. 15 %. 10 %. 25 %. 50 %. 15 %. 10 %. 25 %. 50 %. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is/are the necessary conditions for voltage build up in self excited generator? All of these Poles should contain residual flux. Field winding resistance should be less than critical resistance. Field winding should be properly connected to armature winding. All of these Poles should contain residual flux. Field winding resistance should be less than critical resistance. Field winding should be properly connected to armature winding. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the emf generated by a 4 pole Lap connected DC Motor rotating at 1500 rpm having 1000 conductors and useful flux per pole is 0.4 mWb. 40 volts. 10 volts. 20 volts. 30 volts. 40 volts. 10 volts. 20 volts. 30 volts. ANSWER DOWNLOAD EXAMIANS APP