Electrical Machines In 3 - Φ induction motor some times copper bars are placed deep in the rotor to improve starting torque. improve power factor. improve efficiency. reduce copper loss. improve starting torque. improve power factor. improve efficiency. reduce copper loss. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the field winding connection of DC shunt motor is changed It will run in same direction. It will run in opposite direction. motor will become slow. motor will not run. It will run in same direction. It will run in opposite direction. motor will become slow. motor will not run. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following, voltage regulation may be zero or negative All of these lagging power factor leading power factor unity power factor All of these lagging power factor leading power factor unity power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer has maximum efficiency at 3/4 load. The ratio of iron loss and full load copper loss is 9/16. 4/3. 3/4. 16/9. 9/16. 4/3. 3/4. 16/9. 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 3, 4, 5 2, 4, 5, 6 2, 3, 6 1, 2, 5 3, 4, 5 2, 4, 5, 6 2, 3, 6 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a stepper motor the detente torque means minimum of the static torque with the phase winding unexcited. maximum of the static torque with the phase winding excited. minimum of the static torque with the phase winding excited. maximum of the static torque with the phase winding unexcited. minimum of the static torque with the phase winding unexcited. maximum of the static torque with the phase winding excited. minimum of the static torque with the phase winding excited. maximum of the static torque with the phase winding unexcited. ANSWER DOWNLOAD EXAMIANS APP