Electrical Machines The no load current in a transformer lags the applied voltage by about 75°. 90°. 0°. about 115°. about 75°. 90°. 0°. about 115°. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For higher values of armature, the speed of a DC series motor is Proportional to the square of armature current. Constant. Proportional to armature current. Inversely proportional to armature current. Proportional to the square of armature current. Constant. Proportional to armature current. Inversely proportional to armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direct-on-line (DOL) starters are not suitable for starting large DC motors, because the starting current will be enormously high. the motor may run away. the motor may not start. the starting torque becomes low. the starting current will be enormously high. the motor may run away. the motor may not start. the starting torque becomes low. 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, 3 2, 4 1, 3 1, 4 2, 3 2, 4 1, 3 1, 4 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. 10 volts. 20 volts. 30 volts. 40 volts. 10 volts. 20 volts. 30 volts. 40 volts. 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 sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. sR2 = X2. R2 = s2X2. R2 = sX2. R2 = s2X2. ANSWER DOWNLOAD EXAMIANS APP
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