Electrical Machines What is the increase in the torque expressed as percentage of initial torque, if current drawn by the dc series motor is increased from 10A to 11A? 11% 21% 10% 41% 11% 21% 10% 41% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 240 V, dc shunt motor draws 15 A while supplying the rated load at a speed of 80 rad/s. The armature resistance is 0.5 W and the field winding resistance is 80 W. The external resistance to be added in the armature circuit to limit the armature current to 125% of its rated value is 15.9 Ω 31.1 Ω 31.9 Ω 15.1 Ω 15.9 Ω 31.1 Ω 31.9 Ω 15.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The slight curvature at the lower end of the OCC of a self excited DC generator is due to magnetic inertia. high field resistance. residual flux. high speed. magnetic inertia. high field resistance. residual flux. high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Wave winding is employed in DC machine of high current and low voltage rating. low current and low voltage rating. high current and low voltage rating. low current and high voltage rating. high current and low voltage rating. low current and low voltage rating. high current and low voltage rating. low current and high voltage rating. 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. 30 volts. 20 volts. 40 volts. 10 volts. 30 volts. 20 volts. 40 volts. 10 volts. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator sparking between brushes and commutator surface may be due to under commutation. too rapid reversal of current. over commutation. any of the above. under commutation. too rapid reversal of current. over commutation. any of the above. ANSWER DOWNLOAD EXAMIANS APP
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