Electrical Machines If an additional resistance is connected in series with a DC motor operating at rated speed, the speed of the motor will Reduce. Increase. Remain unaltered. Oscillate around the normal speed. Reduce. Increase. Remain unaltered. Oscillate around the normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the number of poles required, when the frequency is 50Hz and speed of the motor is 500 rpm? 5 24 12 10 5 24 12 10 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starting current of a 3 - Φ induction motor is 5 times the rated current, while rated slip is 4 %, then ratio of starting torque to full load torque is 0.4. 1. 0.8. 0.6. 0.4. 1. 0.8. 0.6. 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 1.8 9 Ω 2 .1 Ω 3.1 Ω 1.79 Ω 1.8 9 Ω 2 .1 Ω 3.1 Ω ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will happen if the the supply terminals are reversed in case of a DC shunt motor? The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The motor will run in reverse direction. The motor will stop. The motor will run much faster in the same direction. The motor will run at its normal speed in the same direction as before. The motor will run in reverse direction. The motor will stop. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two identical loss less series motors connected in series across a dc supply voltage, runs at speed of N1 and N2, then ratio of their output power is 1 : 1. N12 : N22. none. N1 : N2. 1 : 1. N12 : N22. none. N1 : N2. ANSWER DOWNLOAD EXAMIANS APP
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