D.C. series motor
synchronous motor
series motor B. synchronous motor C. Squirrel cage induction motor
Wound round induction motor
Answer is Right!
Answer is Wrong!
Detailed SolutionWhich of the following motors is non-self starting ?
Synchronous motors
32. A synchronous motor can be started by
pony motor
D.
compound motor C. providing damper winding
any of the above
Answer is Right!
Answer is Wrong!
33. 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
remain same
go down
improve
none of the above
Answer is Right!
Answer is Wrong!
34. The speed regulation of a synchronous motor is always
1%
0.50%
positive
zero
Answer is Right!
Answer is Wrong!
Detailed SolutionThe speed regulation of a synchronous motor is always
35. A rotory converter can also be run as a
d.c. shunt motor
d.c. series motor
d.c. compound motor
induction motor E. synchronous motor
Answer is Right!
Answer is Wrong!
36. If one-phase of a 3-phase synchronous motor is short-circuited, motor
will refuse to start
will overheat in spots
will not come upto speed
will fail to pull into step
Answer is Right!
Answer is Wrong!
Detailed SolutionIf one-phase of a 3-phase synchronous motor is short-circuited, motor
37. The construction of a synchronous motor resembles
a series motor
an induction motor
an alternator
a rotary converter
Answer is Right!
Answer is Wrong!
Detailed SolutionThe construction of a synchronous motor resembles
38. As the load is applied to a synchronous motor, the motor takes more armature current because
The increased load has to take more current
The rotor by shifting its phase backward causes motor to take more current
The back e.m.f. decreases causing an increase in motor current
The rotor strengthens the rotating field causing more motor current
Answer is Right!
Answer is Wrong!
39. In which of the following motors the stator and rotor fields rotate simultaneously ?
D.C. motor
Reluctance motor
motor B. Reluctance motor C. Universal motor
Synchronous motor
Answer is Right!
Answer is Wrong!
40. A synchronous motor will always stop when
supply voltage fluctuates
load in motor varies
excitation winding gets disconnected
supply voltage frequency changes
Answer is Right!
Answer is Wrong!