Electrical Machines In case of a dc motor the ratio Eb / E is indicative of efficiency. ratio of starting to running current. ratio of starting to running torque. ratio of input to output voltage. efficiency. ratio of starting to running current. ratio of starting to running torque. ratio of input to output voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the source voltage of a DC motor is increased, which of the following will decrease? Operating speed. Starting torque. Starting torque, operating speed, full load current. Full load current. Operating speed. Starting torque. Starting torque, operating speed, full load current. Full load current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Direction of rotation of DC motor is reversed by Reversing supply connection. Interchanging armature and field connection. Reversing armature connection or field connection. Adding resistance to field circuit. Reversing supply connection. Interchanging armature and field connection. Reversing armature connection or field connection. Adding resistance to field circuit. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A lap wound 4 pole dc motor has 460 conductors. Find the number of parallel paths between the conductors? 2. 6. data provided is insufficient. 4. 2. 6. data provided is insufficient. 4. 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, 2, and 3 1 and 3 1, 2 and 4 2, 3 and 4 1, 2, and 3 1 and 3 1, 2 and 4 2, 3 and 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator in case the brushes are moved so as to bring them in magnetic neutral axis, then, there will be none of above. cross-magnetization as well as demagnetization. cross-magnetisation. demagnetisation. none of above. cross-magnetization as well as demagnetization. cross-magnetisation. demagnetisation. ANSWER DOWNLOAD EXAMIANS APP
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