Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2 and 3 3 only 1, 2, 3 and 4 1, 3 1, 2 and 3 3 only 1, 2, 3 and 4 1, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In alternator, the rotary part is none of these. armature. core. magnetic field poles. none of these. armature. core. magnetic field poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Fifth harmonic component of the induced voltage in three phase AC generator can be eliminated by using a winding pitch of 5 / 6. 6 / 7. 2 / 3. 4 / 5. 5 / 6. 6 / 7. 2 / 3. 4 / 5. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous motor, the damper winding is generally used to prevent hunting and provide the starting torque. provide starting torque only. reduce the eddy currents. reduce noise level only. prevent hunting and provide the starting torque. provide starting torque only. reduce the eddy currents. reduce noise level only. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In shunt dc motor the direction of rotation of the motor will reversed. When either field terminals are reversed or armature terminals are reversed. only field terminals are changed. only armature terminals are reversed. none of above. either field terminals are reversed or armature terminals are reversed. only field terminals are changed. only armature terminals are reversed. none of above. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of a DC Shunt motor if the load is decreased to some extent, what will happen to its speed? The speed will increase gradually. The speed will increase in proportion to reduction in load. The speed will increase abruptly. The speed will remains almost constant. The speed will increase gradually. The speed will increase in proportion to reduction in load. The speed will increase abruptly. The speed will remains almost constant. ANSWER DOWNLOAD EXAMIANS APP