Electrical Machines Armature reaction in a DC machine is in direct opposition to the main poles. makes an angle with the main pole axis which is load dependent. makes an angle of 90° with the main pole axis. is in the same direction as the main poles. is in direct opposition to the main poles. makes an angle with the main pole axis which is load dependent. makes an angle of 90° with the main pole axis. is in the same direction as the main poles. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the excitation is increased, the power factor is unity power factor leading power factor None of these lagging power factor unity power factor leading power factor None of these lagging power factor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two synchronous generators operating in parallel 200 MW and 400 MW respectively. The drooping characteristics of their governors are identical as 4% from no load to full load. Consider the governors operating at 50Hz on no load. What is the operating frequency, if the load is 600 MW? 48 Hz 48.5 Hz 50 Hz 45 HZ 48 Hz 48.5 Hz 50 Hz 45 HZ ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Breather is provided in a transformer to provide cold air in transformer. absorb moisture of air during breathing. filter the transformer oil. absorb moisture from air entering in transformer. provide cold air in transformer. absorb moisture of air during breathing. filter the transformer oil. absorb moisture from air entering in transformer. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Satisfactory commutation of DC machine requires All of these brushes should smoothly run in the holders. brushes should be of proper grade and size. smooth, concentric commutator properly undercut. All of these brushes should smoothly run in the holders. brushes should be of proper grade and size. smooth, concentric commutator properly undercut. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In case of DC Shunt Motor electromagnetic torque developed is Proportional to the square of armature current. Proportional to the armature current. Inversely proportional to the armature current. None of above. Proportional to the square of armature current. Proportional to the armature current. Inversely proportional to the armature current. None of above. ANSWER DOWNLOAD EXAMIANS APP