Electrical Machines The material used for commutator brushes is mostly copper. mica. carbon. cast iron. copper. mica. carbon. cast iron. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Unbalance 3 - Φ stator currents cause All of these heating of rotor. vibrations. double frequency currents in the rotor. All of these heating of rotor. vibrations. double frequency currents in the rotor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 1.79 Ω 2 .1 Ω 3.1 Ω 1.8 9 Ω 1.79 Ω 2 .1 Ω 3.1 Ω 1.8 9 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Ward Leonard control provides speed control in one direction only. above rated speed. below rated speed. in both direction. in one direction only. above rated speed. below rated speed. in both direction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines As compared to DOL starting, a cage induction motor with star-delta starting shall have smoother acceleration. more starting time. more starting torque. reduced starting current. smoother acceleration. more starting time. more starting torque. reduced starting current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3 - Φ, 6 pole, 50 Hz IM has a rotor speed of 987 rpm find rotor frequency? 0.75 Hz. 60 Hz. 0.65 Hz. 0.70 Hz. 0.75 Hz. 60 Hz. 0.65 Hz. 0.70 Hz. ANSWER DOWNLOAD EXAMIANS APP