A three point starter is considered suitable for Shunt as well as compound motors All D.C. motors Shunt motors Shunt, compound and series motors TRUE ANSWER : ? YOUR ANSWER : ?
In the dc motor the iron losses occur in Armature Brushes Commutator Field TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following in a dc motor, can sustain the maximum temperature rise? Field winding Slip rings Commutator Armature winding TRUE ANSWER : ? YOUR ANSWER : ?
The most suitable motor for elevators is the ____ motor. Differentially compuonded Shunt Series Cummulative compounded TRUE ANSWER : ? YOUR ANSWER : ?
The variable resistor shunting the field of a dc series motor is called a Armature divertor Potential divider Voltage regulator Field divertor TRUE ANSWER : ? YOUR ANSWER : ?
If the speed of a dc shunt motor is increased the back emf of the motor will Become zero Increase Remains same Decrease TRUE ANSWER : ? YOUR ANSWER : ?
For the same H.P. rating and full load speed, following motor has poor starting torque Shunt Series Cumulatively compounded Differentially compounded TRUE ANSWER : ? YOUR ANSWER : ?
Which of the following law can be used to determine the direction of rotation of dc motor? Fleming's left hand rule Coloumb's law Faraday's law Lenz's law TRUE ANSWER : ? YOUR ANSWER : ?
As there is no back e.m.f. at the instant of starting a D.C. motor, in order to prevent a heavy current from flowing though the armature circuit A resistance is connected in series with armature A high value resistor is connected across the field winding A resistance is connected parallel to the armature Armature is temporarily open circuited TRUE ANSWER : ? YOUR ANSWER : ?
Excessive sparking at brushes may be caused due to Worn bearings Misaligment of machine Loose coupling Dirt on the commutator TRUE ANSWER : ? YOUR ANSWER : ?