Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5Ω and back back emf 200 V is 44 A. 40 A. 440 A. 400 A. 44 A. 40 A. 440 A. 400 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For an ideal transformer the winding should have maximum resistance on primary side and least resistance on secondary side minimum resistance on primary side and maximum resistance on secondary side no ohmic resistance on either side equal resistance on primary and secondary side maximum resistance on primary side and least resistance on secondary side minimum resistance on primary side and maximum resistance on secondary side no ohmic resistance on either side equal resistance on primary and secondary side ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC series motor has which of the following characteristics? Can be started easily without load. Has its field winding consinting of thick wire and less no of turns. Has a almost constant speed. Has a poor torque. Can be started easily without load. Has its field winding consinting of thick wire and less no of turns. Has a almost constant speed. Has a poor torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1 and 3 2, 3 and 4 1, 2 and 4 1, 2, and 3 1 and 3 2, 3 and 4 1, 2 and 4 1, 2, and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Synchronous condensers are used to reduce hunting All of these improve starting torque improve the power factor reduce hunting All of these improve starting torque improve the power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase slip ring induction motor is wound for 4 poles on stator and 6 poles on the rotor. When 3-phase balanced voltage source at 50 Hz is applied, it will run at 1000 rpm zero speed 750rpm 1500 rpm 1000 rpm zero speed 750rpm 1500 rpm ANSWER DOWNLOAD EXAMIANS APP