Electrical Machines A 4 pole DC generator runs at 750 rpm and generate an emf of 240 V. The armature is wave wound and has 792 conductors. If the total flux from each pole is 0.0145 Wb. What is the leakage co-efficient? 1.4. 1.2. 1.8. 1.5. 1.4. 1.2. 1.8. 1.5. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider the following statements regarding dc machines : 1. possible resistance of shunt-field winding is 1 Ω 2. possible resistance of series-field winding is 1 Ω 3. electrographite brushes are used for 230 V, 10 A machines 4. Copper-graphite brushes are used for 230 V, 10 A machines 5. Possible armature-circuit resistance is 1 Ω From these, the correct statements are 2, 3 , 5 2, 4 ,5 1, 3, 5 1, 4 2, 3 , 5 2, 4 ,5 1, 3, 5 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The ___________________ generator has the poorest voltage regulation. shunt. under-compounded. differential compounded. over compounded. shunt. under-compounded. differential compounded. over compounded. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Armature reaction depends on which of the following? power factor of load both 1 and 2 None of these magnitude of load current power factor of load both 1 and 2 None of these magnitude of load current ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes 1/2 of the initial value twice the initial value 1/4 of the intial value 4 time the initial value 1/2 of the initial value twice the initial value 1/4 of the intial value 4 time the initial value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In synchronous generator V curve is drawn between field current on X-axis and armature current on Y-axis. field current on Y-axis and armature current on X-axis. either of these. field current on X-axis and power factor on Y-axis. field current on X-axis and armature current on Y-axis. field current on Y-axis and armature current on X-axis. either of these. field current on X-axis and power factor on Y-axis. ANSWER DOWNLOAD EXAMIANS APP