Electrical Machines In a transformer zero voltage regulation is achieved at a load power factor which is lagging zero unity leading lagging zero unity leading ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The direction of generated emf in the armature coil of a DC machine is 1. the same as that of the current in a generator 2. the same as that of the current in a motor 3. opposite to that of the current in a generator 4. opposite to that of the current in a motor From these, the correct answer is 2, 3 1, 3 2, 4 1, 4 2, 3 1, 3 2, 4 1, 4 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC generator on no-load, the air gap flux distribution in space is sinusoidal. triangular. flat topped. pulsating. sinusoidal. triangular. flat topped. pulsating. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When the rotor of a 3 phase induction motor is blocked then the slip is 1. 0.7. 0.3. 0.54. 1. 0.7. 0.3. 0.54. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines φA DC shunt machine generates 250 V on open circuit at 1000 RPM. Armature resistance is 0.5 Ω, field resistance 250 Ω. When running as a motor takes 4 A at 250 V. Calculate the speed when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 970 RPM 960 RPM 940 RPM 920 RPM 970 RPM 960 RPM 940 RPM 920 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The squirrel cage induction motors are provided with blades in order to eliminate noise. none of these. facilitate cooling of rotor. balance the rotor dynamically. eliminate noise. none of these. facilitate cooling of rotor. balance the rotor dynamically. ANSWER DOWNLOAD EXAMIANS APP