Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by sf. sf / 2. f / s. s2. sf. sf / 2. f / s. s2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Conservator tank is used for better cooling of transformer. to take up the expansion of oil due to temperature rise. to act as an oil storage. None of these for better cooling of transformer. to take up the expansion of oil due to temperature rise. to act as an oil storage. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, the demagnetizing effect of armature reaction is due to component of armature mmf along field axis non-sinusoidal nature of armature mmf magnetic saturation in half of the field pole uneven air-gap length component of armature mmf along field axis non-sinusoidal nature of armature mmf magnetic saturation in half of the field pole uneven air-gap length ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If an additional resistance is connected in series with a DC series motor operating at rated speed, the speed of the motor will Oscillate around the normal speed. Reduce. Increase. Remain unaltered. Oscillate around the normal speed. Reduce. Increase. Remain unaltered. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature reaction mmf in a DC machines has a form of trapezoidal. rectangular. sinusoidal. triangular. trapezoidal. rectangular. sinusoidal. triangular. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator sparking between brushes and commutator surface may be due to under commutation. over commutation. any of the above. too rapid reversal of current. under commutation. over commutation. any of the above. too rapid reversal of current. ANSWER DOWNLOAD EXAMIANS APP