An induction motor is, in general analogous to None of these auto transformer. two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. TRUE ANSWER : ? YOUR ANSWER : ?
A 220 V, DC shunt motor is operating at a speed of 1440 rpm. The armature resistance is 1.0 Ω and armature current is 10 A. of the excitation of the machine is reduced by 10%, the extra resistance to be put in the armature circuit to maintain the same speed and torque will be 3.1 Ω 2 .1 Ω 1.8 9 Ω 1.79 Ω TRUE ANSWER : ? YOUR ANSWER : ?
In an induction motor, what is the ratio of rotor input to rotor copper loss? 1-S S 1/(1-S) 1/S TRUE ANSWER : ? YOUR ANSWER : ?
The polarity of a DC generator can be reversed by increasing field current. reversing the field current. any of above. reversing field electric current as well as direction of rotation. TRUE ANSWER : ? YOUR ANSWER : ?
In which of the following, voltage regulation may be zero or negative lagging power factor unity power factor leading power factor All of these TRUE ANSWER : ? YOUR ANSWER : ?
The current drawn by the armature of DC motor is directly proportional to The speed of motor. The torque required. None of above. The voltage across the terminals. TRUE ANSWER : ? YOUR ANSWER : ?
The emf induced in the dc generator armature winding is DC AC AC and DC None of these TRUE ANSWER : ? YOUR ANSWER : ?
In a DC Shunt Motor if the load current increases then field flux remains constant. decreases. decreases increases. TRUE ANSWER : ? YOUR ANSWER : ?
Armature of DC machine is made of silicon steel. conducting material. insulating material. non-ferrous material. TRUE ANSWER : ? YOUR ANSWER : ?
Eb/Vt ratio of a DC motor is an indication of efficiency. speed regulation. running torque. starting torque. TRUE ANSWER : ? YOUR ANSWER : ?