Electrical Machines The armature MMF waveform of a DC machine is sinusoidal. pulsating. triangular. rectangular. sinusoidal. pulsating. triangular. rectangular. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machine shape of armature MMF wave is? Peaky in nature. Triangular and directed towards main pole. Saddle shape. Triangular and directed towards brush axis. Peaky in nature. Triangular and directed towards main pole. Saddle shape. Triangular and directed towards brush axis. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What will be the eddy current loss if the supply frequency of a transformer becomes double? Doubled. Remains same. Four times. Eight times. Doubled. Remains same. Four times. Eight times. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The principal of starting of 3 - Φ IM is similar to capacitor run IM. synchronous motor. transformer with short-circuited secondary. repulsion motor type starting. capacitor run IM. synchronous motor. transformer with short-circuited secondary. repulsion motor type starting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 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 efficiency when running as a motor taking 40 A at 250 V. Armature reaction weakens the field by 4%. 67.5% 72.5% 78.5% 82.5% 67.5% 72.5% 78.5% 82.5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In which of the following, voltage regulation may be zero or negative unity power factor lagging power factor All of these leading power factor unity power factor lagging power factor All of these leading power factor ANSWER DOWNLOAD EXAMIANS APP