Electrical Machines If any two leads from slip rings are interchanged in a 3 - Φ induction motor, the motor will not run. continue running in the same direction as before. run in a direction opposite to previous one. get damaged. not run. continue running in the same direction as before. run in a direction opposite to previous one. get damaged. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature coil is short circuited by brushes when it lies along neutral axis. in none of above positions. along field axis. in any of above positions. along neutral axis. in none of above positions. along field axis. in any of above positions. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes twice the initial value 1/2 of the initial value 1/4 of the intial value 4 time the initial value twice the initial value 1/2 of the initial value 1/4 of the intial value 4 time the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc generator operating on load with its brushes on the geometrical neutral axis (GNA), the magnetic neutral axis (MNA) is shifted in the direction of rotation. Now, if the brushes are given a lead of 90° (electrical), then the MNA will coincide with the GNA shift forward by 90° shift forward by more than 90° shift forward by less than 90° coincide with the GNA shift forward by 90° shift forward by more than 90° shift forward by less than 90° ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two dc machines A and B, using the same conductor material, have armature circuit resistances of 0.4 Ω and 1.2 Ω respectively. Of the two machines, B is bigger than A for the same current rating both are of the same size for the same current rating A is bigger than B for the same current rating A is bigger than B for the same voltage rating B is bigger than A for the same current rating both are of the same size for the same current rating A is bigger than B for the same current rating A is bigger than B for the same voltage rating ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the magnetization characteristics of a dc generator : 1. It represents the variation of field flux with field current. 2. Variation of open-circuit terminal voltage with field current is independent of speed 3. It is non-linear from zero to rated field current 4. It helps to determine the critical field resistance at a given speed 5. It always starts from the origin Which of these statements are correct ? 2, 3 and 4 1 and 4 1, 2 and 5 3 and 5 2, 3 and 4 1 and 4 1, 2 and 5 3 and 5 ANSWER DOWNLOAD EXAMIANS APP