Bissoy.com
Doctors Medicines MCQs Q&A

As the load is applied to a synchronous motor, the motor takes more armature current because

As the load is applied to a synchronous motor, the motor takes more armature current because Correct Answer The rotor by shifting its phase backward causes motor to take more current

Related Questions

Consider the following statements: In the above figure, the curves pertain to the DC motor A. Speed vs Armature current characteristic of a DC shunt motor B. Torque vs Armature current characteristic of a DC shunt motor C. Speed vs Armature current characteristic of a DC series motor D. Torque vs Armature current characteristic of a DC series motor
In case of synchronous motor, which of the following are true? a. Synchronous motor is not self-starting b. If the rotor poles are excited by field current and the stator terminals are connected to AC supply, motor vibrates. c. Variable frequency supply is used to start synchronous motor. d. By using frequency converter, a synchronous motor can be brought from standstill to its desired speed.
Which of the following statements are true? a. As load increases armature current decreases, regardless of excitation. b. For under and over excited motors, power factor tends to approach zero with increase in load c. With normal excitation when load is increased, change in armature current is greater than in power factor which tends to become increasingly leading. d. Both with under and over excitation, change in power factor is greater than in armature current with increase in load.
A three-phase cylindrical rotor synchronous generator has a synchronous reactance Xs and a negligible armature resistance. The magnitude of per phase terminal voltage is VA and the magnitude of per phase induced emf is EA. Considering the following two statements, P and Q, P: For any three-phase balanced leading load connected across the terminals of this synchronous generator, VA is always more than EA Q: For any three-phase balanced lagging load connected across the terminals of this synchronous generator, VA is always less than EA Which of the following options is correct?
Consider the following statements regarding synchronous machines: 1. When a synchronous motor is over-excited, its back emf is greater than the supply voltage 2. When a synchronous motor is over-excited, its power factor is leading 3. Synchronous motor is used as capacitor where load is so large that construction of a static capacitor is impractical Which of these statements are correct?
A synchronous motor installed at the receiving end substation operates with such an excitation that it takes power at lagging power factor. Now if the applied voltage of the synchronous motor goes down, the power factor of the synchronous motor will
Consider the following statements with respect to synchronous machines. State whether these statements are true or false. (a) Armature reaction is demagnetising when a generating machine supplies zero power factor lagging current. (b) Armature reaction is magnetising when a generating machine supplies zero power factor leading current. (c) Armature reaction is mostly cross-magnetising, though it has a small demagnetising component, when a generating machine supplies unity power factor current.
400-V dc shunt motor takes a current of 5.6 A on no-load and 68.3 A on full-load. Armature reaction weakens the field by 3%. What is the ratio of full-load speed to no-load speed? Given: Ra = 0.18 Ω, brush voltage drop= 2 V, Rf = 200 Ω.
In an alternator, the armature winding is kept stationary while the field winding is kept rotating for the following reasons: 1. Armature handles very large current and high voltage 2. Armature fabrication, involving deep slots to accommodate large coils, is easy if armature is kept stationary 3. It is easier to cool the stator than the rotor Which of the above reasons are correct?
A 4-pole wave wound DC motor drawing an armature current of 20 A has provided with 360 armature conductors. If the flux per pole is 0.015 Wb then the torque developed by the armature of motor is _______