Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5 Ω and back emf of 200 V is 440 A. 40 A. 400 A. 44 A. 440 A. 40 A. 400 A. 44 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When R2 is rotor resistance, X2 the rotor reactance at supply frequency and s the slip, then the condition for maximum torque under running condition will be R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 500 V, 120 KW, 50 Hz, star connected synchronous motor operating at 0.8 power factor leading has full load efficiency of 91%. The armature resistance is equal to 0.08Ω. The magnitude of armature current is nearly equal to 190 A. 240 A. 173 A. 127 A. 190 A. 240 A. 173 A. 127 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuiting is caused in the armature winding due to failure of insulation between two commutator bars. failure of insulation between two turns of coil. grounding of two or more turns of the same coil. any of above. failure of insulation between two commutator bars. failure of insulation between two turns of coil. grounding of two or more turns of the same coil. any of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The teeth in the armature of a DC machines are sometimes skewed. This is done to reduce hysteresis loss. vibrations. copper loss. eddy electric current loss. hysteresis loss. vibrations. copper loss. eddy electric current loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Generator works on the principle of production dynamically induced emf. static induced emf. None of these both A and B. dynamically induced emf. static induced emf. None of these both A and B. ANSWER DOWNLOAD EXAMIANS APP
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