Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. The frequency of rotor current is 0 Hz 1 Hz 50 Hz 5 Hz 0 Hz 1 Hz 50 Hz 5 Hz ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase slip ring induction motor is wound for 4 poles on stator and 6 poles on the rotor. When 3-phase balanced voltage source at 50 Hz is applied, it will run at 1000 rpm zero speed 1500 rpm 750rpm 1000 rpm zero speed 1500 rpm 750rpm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements about commutating poles which are fitted on most large dc Shunt motors: 1. The commutating poles are placed in the geometric neutral plane and their number is usually Equal to the number of main poles 2. The winding on the commutating poles is connected in series with the shunt-field winding on the main poles 3. The polarity of the commutating pole must be that of the next pole further ahead 4. The commutating poles neutralize the reactance voltage produced in the coil undergoing Commutation. Of these statements, 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct 1, 2 and 4 are correct 1 and 4 are correct 2, 3 and 4 are correct 1, 2 and 3 are correct ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The noise resulting from vibrations of lamination set by magnetic forces, is termed as hum. boo. zoom. magnetostriction. hum. boo. zoom. magnetostriction. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Lap winding is prefered for which type of machines? high current and high voltage high current and low voltage low current and low voltage low current and high voltage high current and high voltage high current and low voltage low current and low voltage low current and high voltage ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Neglecting all losses, the developed torque (T) of DC separately excited motor, operating under constant terminal voltage is reduced to its output power (P) as T ∝ √P. T is independent of P. T ∝ P. T2 ∝ P3. T ∝ √P. T is independent of P. T ∝ P. T2 ∝ P3. ANSWER DOWNLOAD EXAMIANS APP