Electrical Machines If the load current and flux of a DC motor are held constant and voltage applied across it armature is increased by 5%, the speed of the motor will Reduce by 5%. Remain unchanged. Depends on other factor. Increase by 5%. Reduce by 5%. Remain unchanged. Depends on other factor. Increase by 5%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following motors DC excitation is not required? 3-phase synchronous generator reluctance motor hysteresis motor 3-phase synchronous motor 3-phase synchronous generator reluctance motor hysteresis motor 3-phase synchronous motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 2 KVA transformer has iron loss of 150 W and full load copper loss of 250 W. The maximum efficiency of the transformer would occur when the total loss is 500 W 300 W 250 W 400W 500 W 300 W 250 W 400W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine, the armature windings are placed on the rotor because of necessity for generation of voltage. development of torque. electromechanical energy conversion. commutation. generation of voltage. development of torque. electromechanical energy conversion. commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A three phase 400 V, 6 pole, 50 Hz, squirrel cage induction motor is running at a slip of 5%. The speed of stator magnetic field with respect to rotor magnetic field and speed of rotor w.r.t stator magnetic field are zero , - 50 rpm. 1000 rpm, - 50 rpm. zero, 950 rpm. 1000 rpm, 950 rpm. zero , - 50 rpm. 1000 rpm, - 50 rpm. zero, 950 rpm. 1000 rpm, 950 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The sparking at the the brushes, in a DC machines is due to armature reaction. high resistance of carbon brushes. reactance voltage. presence of commutator. armature reaction. high resistance of carbon brushes. reactance voltage. presence of commutator. ANSWER DOWNLOAD EXAMIANS APP
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