Electrical Machines The direction of rotation of a DC motor can be determent by Flemings right hand rule. Amperes law. Lenzs law. Flemings left hand rule. Flemings right hand rule. Amperes law. Lenzs law. Flemings left hand rule. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An induction motor is, in general analogous to two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. auto transformer. None of these two winding transformer with secondary open circuited. two winding transformer with secondary short circuited. auto transformer. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements : 1. interpole windings are connected in series with armature windings 2. polarity of interpoles must be the same as that of the main poles in advance 3. distortion of the main field under the pole shoes is not affected by the use of interpoles From above, the correct answer is 2 and 3 1 and 2 1 and 3 1 alone 2 and 3 1 and 2 1 and 3 1 alone ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Value of specific electric loading of Induction motor is in the range of 5000 - 45000 ampere conductor / metre. 40 - 400 ampere conductor / metre. 30000 - 100000 ampere conductor / metre. 400 - 4000 ampere conductor / metre. 5000 - 45000 ampere conductor / metre. 40 - 400 ampere conductor / metre. 30000 - 100000 ampere conductor / metre. 400 - 4000 ampere conductor / metre. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The counter (or back) emf in a dc machine is 1. the same as generated emf in a dc motor 2. proportional to field flux and armature speed 3. not the same as generated emf in a dc motor 4.inversely proportional to field flux 5. proportional to number of armature conductors 6. constant from no load to full load From these, the correct answer is 1, 2, 5 2, 4, 5, 6 2, 3, 6 3, 4, 5 1, 2, 5 2, 4, 5, 6 2, 3, 6 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direct-on-line (DOL) starters are not suitable for starting large DC motors, because the motor may run away. the motor may not start. the starting current will be enormously high. the starting torque becomes low. the motor may run away. the motor may not start. the starting current will be enormously high. the starting torque becomes low. ANSWER DOWNLOAD EXAMIANS APP
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