Electrical Machines The sparking at the the brushes, in a DC machines is due to high resistance of carbon brushes. armature reaction. presence of commutator. reactance voltage. high resistance of carbon brushes. armature reaction. presence of commutator. reactance voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series generator is connected in series to a feeder having 0.5Ω resistance to boost the voltage. The induced voltage is given by Eg = 0.6Ia, Ra = 0.2Ω and Rs = 0.3Ω. Find the voltage boosted by the generator, when delivering 400 Amp? 60 V. 90 V. 30 V. 40 V. 60 V. 90 V. 30 V. 40 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In electric locomotive which of the following motor are used ? Shunt motor. Separately compound motor. DC series motor. Synchronous motor. Shunt motor. Separately compound motor. DC series motor. Synchronous motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When maximum starting torque is obtained, rotor power is ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mmf produced by rotor currents of a 3 - Φ induction motor rotates at the speed of rotor in the air gap. rotates at synchronous speed with respect to rotor. rotates at slip speed with respect to stator mmf. is at standstill with respect to stator mmf. rotates at the speed of rotor in the air gap. rotates at synchronous speed with respect to rotor. rotates at slip speed with respect to stator mmf. is at standstill with respect to stator mmf. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The air gap between stator and the rotor of the 3 - φ induction motor is kept as small as possible. depends on the material of stator and the rotor. as wide as possible. air gap does not matter. as small as possible. depends on the material of stator and the rotor. as wide as possible. air gap does not matter. ANSWER DOWNLOAD EXAMIANS APP