Electrical Machines What is the mechanical power developed by a DC series motor is maximum? Back emf is equal to zero. None of above. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. Back emf is equal to zero. None of above. Back emf is equal to half the applied voltage. Back emf is equal to applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What are slot wedges in a DC machine made of? Mild steel. Cast iron. Silicon steel. Fibre. Mild steel. Cast iron. Silicon steel. Fibre. 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. 2 / 3. 4 / 5. 6 / 7. 5 / 6. 2 / 3. 4 / 5. 6 / 7. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the ripples in the direct emf generated are reduced by employing graphite brushes. commutator with large number of segments. carbon brushes. equalizer rings. graphite brushes. commutator with large number of segments. carbon brushes. equalizer rings. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Interpoles in a DC motor must be Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the behind main pole in the direction of rotation of armature. Shunt excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. Series excited and should have the same polarity as that of the ahead main pole in the direction of rotation of armature. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC Shunt Motor electromagnetic torque developed is None of above. Inversely proportional to the armature current. Proportional to the armature current. Proportional to the square of armature current. None of above. Inversely proportional to the armature current. Proportional to the armature current. Proportional to the square of armature current. ANSWER DOWNLOAD EXAMIANS APP