Electrical Machines If peak value of phase mmf is F max , then peak value of the rotating field caused by three phase is (1/2)Fmax. Fmax. (3/2)Fmax. 3Fmax. (1/2)Fmax. Fmax. (3/2)Fmax. 3Fmax. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A simple method of increasing the voltage of a DC generator is to increase the number of turns in field coil. increase the source frequency. increase the number of turns in armature coil. increase the speed of shaft rotation. increase the number of turns in field coil. increase the source frequency. increase the number of turns in armature coil. increase the speed of shaft rotation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A single-phase transformer has its maximum efficiency at 60 percent of full load. At full load copper loss will be less than core loss. equal to core loss. more than core loss. zero. less than core loss. equal to core loss. more than core loss. zero. 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 920 RPM 940 RPM 960 RPM 970 RPM 920 RPM 940 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Two transformers operating in parallel will share the load depending on their efficiency ratings per unit impedance leakage reactance efficiency ratings per unit impedance leakage reactance ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following motor used in hair dryers? Split phase IM. Cage induction motor. Shaded pole IM. Synchronous motors. Split phase IM. Cage induction motor. Shaded pole IM. Synchronous motors. ANSWER DOWNLOAD EXAMIANS APP
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