Electrical Machines An induction motor having 8 poles runs at 727.5 rpm. If the supply frequency is 50Hz, the emf in the rotor will have a frequency of 51.5Hz 48.5Hz 2.5Hz 1.5Hz 51.5Hz 48.5Hz 2.5Hz 1.5Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature resistance of a permanent magnet dc motor is 0.8 Ohm. At no load, the motor draws 1.5 A from a supply voltage of 25 V and runs at 1500 rpm. The efficiency of the motor while it is operating on load at 1500 rpm drawing a current of 3.5 A from the same source will be 48.0%. 57.1%. 88.8%. 59.2%. 48.0%. 57.1%. 88.8%. 59.2%. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motors has low ratings only? Capacitor start Capacitor run Resistance split phase Shaded pole Capacitor start Capacitor run Resistance split phase Shaded pole ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3-phase induction motor, if the supply voltage and frequency are reduced by the same ratio, then slip at which maximum torque occurs is more and maximum torque decreases less and maximum torque decreases more and maximum torque remains constant less and maximum torque increases more and maximum torque decreases less and maximum torque decreases more and maximum torque remains constant less and maximum torque increases ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Motor is driving a constant load torque having armature resistance of 0.25 Ω and armature current of 60 A having connected to a voltage of 230 V. Now a resistance of 1 ohm is added into the armature circuit. The ratio of their speed will be 0.62. 1.24. 0.72. 0.25. 0.62. 1.24. 0.72. 0.25. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor is used in grinders? Capacitor start IM. Capacitor start capacitor run IM. Synchronous motor. Split phase IM. Capacitor start IM. Capacitor start capacitor run IM. Synchronous motor. Split phase IM. ANSWER DOWNLOAD EXAMIANS APP