Electrical Machines A 3 - Φ, 4 pole, 50 Hz induction motor 4 % slip, calculate frequency of the rotor emf? 2 Hz. 50 Hz. 10 Hz. 3 Hz. 2 Hz. 50 Hz. 10 Hz. 3 Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The air gap between the yoke and armature is dc machine is kept very small to achieve a stronger magnetic field. to avoid locking of the armature. to avoid over heating. All of these to achieve a stronger magnetic field. to avoid locking of the armature. to avoid over heating. All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the magnetization characteristics of a dc generator : 1. It represents the variation of field flux with field current. 2. Variation of open-circuit terminal voltage with field current is independent of speed 3. It is non-linear from zero to rated field current 4. It helps to determine the critical field resistance at a given speed 5. It always starts from the origin Which of these statements are correct ? 3 and 5 1, 2 and 5 2, 3 and 4 1 and 4 3 and 5 1, 2 and 5 2, 3 and 4 1 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field circuit of a DC shunt motor is opened The armature current will reduce. The speed of motor will be reduced. DC Shunt Motor The motor will attain dangerously high speed. The armature current will reduce. The speed of motor will be reduced. DC Shunt Motor The motor will attain dangerously high speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3- phase synchronous motor can operate over a wide range of power factors i.e. from lagging to leading power factor. This is achieved by changing the load. changing the field excitation. varying the applied voltage. varying the speed. changing the load. changing the field excitation. varying the applied voltage. varying the speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Wave winding is prefered for which of the following rating? high current and high voltage low current and low voltage high current and low voltage low current and high voltage high current and high voltage low current and low voltage high current and low voltage low current and high voltage ANSWER DOWNLOAD EXAMIANS APP
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