Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes twice the initial value 1/4 of the intial value 1/2 of the initial value 4 time the initial value twice the initial value 1/4 of the intial value 1/2 of the initial value 4 time the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For successful parallel operation of two single phase transformers, the most essential condition is that their turn- ratios are exactly equal percentage impedances are equal polarities are properly connected KVA ratings are equal turn- ratios are exactly equal percentage impedances are equal polarities are properly connected KVA ratings are equal ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Type of single phase motor having highest power factor at full load is split phase. shaded pole type. capacitor start. capacitor run. split phase. shaded pole type. capacitor start. capacitor run. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding the speed control of dc motors : 1. ward-leonard method is suitable forconstant-torque drives 2. Ward-leonard method is suitable for constant-power drives 3. field-control method facilitates speed control below base speed 4. Armature-resistance control method is more efficient than ward-leanard method 5. Field-control method is suitable for constant-torque drives 6. Armature-resistance control method is suitable for constant-torque drives From these, the correct answer is 1, 3, 5 1, 2, 6 1, 4, 6 1, 2, 5 1, 3, 5 1, 2, 6 1, 4, 6 1, 2, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An electric motor with constant output power will have a torque speed characteristics in the form of a Straight line parallel to the speed axis. Straight line through the origin. Rectangular hyperbola Circle about the origin. Straight line parallel to the speed axis. Straight line through the origin. Rectangular hyperbola Circle about the origin. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The output voltage of a DC generator is E = V + IaRa. E = V + Ra. E = V – IaRa. E = V + Ia. E = V + IaRa. E = V + Ra. E = V – IaRa. E = V + Ia. ANSWER DOWNLOAD EXAMIANS APP
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