Electrical Machines In a DC machine the armature mmf is stationary with respect to field poles. rotating with respect to field poles. stationary with respect to armature. rotating with respect to field poles as well as armature. stationary with respect to field poles. rotating with respect to field poles. stationary with respect to armature. rotating with respect to field poles as well as armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ f/φ E ∝ φ/f E ∝ 1/(φf) E ∝ φf E ∝ f/φ E ∝ φ/f E ∝ 1/(φf) E ∝ φf 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 : 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine 72 number of coils are used. Find the number of commutator segments required? 36 74 72 37 36 74 72 37 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage regulation of transformer is given by (E2 - V2) / V2 (V2 - E2) / E2 (E2 - V2) / E2 (V2 - E2) / V2 (E2 - V2) / V2 (V2 - E2) / E2 (E2 - V2) / E2 (V2 - E2) / V2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Speed of DC motor can be controlled by varying applied voltage. its flux oer pole. all of these. resistance of armature culture. applied voltage. its flux oer pole. all of these. resistance of armature culture. ANSWER DOWNLOAD EXAMIANS APP