Electrical Machines A 10KVA auto transformer, turn ratio is 0.4. Find the power transferred inductively? 4 KVA 10 KVA 6 KVA 0 KVA 4 KVA 10 KVA 6 KVA 0 KVA ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A transformer core is made up of a silicon steel laminations which has maximum flux density 1 Tesla. If it was cold rolled grain oriented its flux density increases to 1.6 Tesla. What is the saving in core size or area due to cold rolled grain oriented process? 68% 60% 38% 40% 68% 60% 38% 40% 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%. 920 RPM 940 RPM 960 RPM 970 RPM 920 RPM 940 RPM 960 RPM 970 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase, 50 Hz, 4 pole induction motor is running at 1440 rpm. Find the rotor efficiency? 96% 95% 92% 94% 96% 95% 92% 94% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The efficiency of a transformer is mainly dependent on core losses. stray losses. dielectric losses. copper losses. core losses. stray losses. dielectric losses. copper losses. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed regulation of a DC motor is given as NnL/NfL. NnL − NfL. (NfL − NnL)/NnL. (NnL − NfL)/NfL. NnL/NfL. NnL − NfL. (NfL − NnL)/NnL. (NnL − NfL)/NfL. ANSWER DOWNLOAD EXAMIANS APP
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