Electrical Engineering Questions And Answers :: Dc Motors: part5

Electrical Engineering : Dc Motors QUESTIONS AND ANSWERS :: part5 : 11 to 15

Following Electrical Engineering Multiple choice objective type questions and answers will help you in BSNL JTO, GATE 2024 and IES 2024 examinations :

11.If a D.C. shunt motor is working at full load and if shunt field circuit suddenly opens

this will make armature to take heavy current, possibly burning it
this will result in excessive speed, possibly destroying armature due to excessive centrifugal stresses
nothing will happen to motor
motor will come to stop

12.During rheostat braking of D.C. series motors

motor is run as a generator
motor is reversed in direction
motor is run at reduced speed
motor is run as a generator

13.Hopkinson's test on D.C. machines is conducted at

part load

14.The condition for maximum efficiency for a D.C. generator is

eddy current losses = stray losses
hysteresis losses = eddy current losses
copper losses = 0
variable losses = constant losses

15.D.C. generators are installed near the load centres to reduce

iron losses
line losses
corona losses

More Dc Motors QUESTIONS AND ANSWERS available in next pages

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