Electrical Machines In a DC generator if field winding attains the critical resistance field winding will burn. machine will generate maximum voltage. the voltage generated will be zero. machine will generate maximum power. field winding will burn. machine will generate maximum voltage. the voltage generated will be zero. machine will generate maximum power. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A load of 900 lbs is to be raised with a lift car weighting 855 lbs at a speed of 110 feet per minute, the over balance being 40 % and percentage efficiency 45 %. Find the horse power of the motor without counterweight 150. 170. 160. 180. 150. 170. 160. 180. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of the rotor bars of dc motors are laminated to reduce hysteresis loss. to reduce mechanical losses. to reduce eddy current loss. to provide better flux linkage. to reduce hysteresis loss. to reduce mechanical losses. to reduce eddy current loss. to provide better flux linkage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 4 1, 3 2, 3 1, 4 2, 4 1, 3 2, 3 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a DC Shunt motor if the load is decreased to some extent, what will happen to its speed? The speed will increase in proportion to reduction in load. The speed will remains almost constant. The speed will increase gradually. The speed will increase abruptly. The speed will increase in proportion to reduction in load. The speed will remains almost constant. The speed will increase gradually. The speed will increase abruptly. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For small value armature current Ia the torque developed by a DC series motor is proportional to 1/Ia. Ia. √Ia. Ia2. 1/Ia. Ia. √Ia. Ia2. ANSWER DOWNLOAD EXAMIANS APP
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