Electrical Machines In a synchronous machine, if φ is the flux per pole and f is the frequency of the emf induced E then E ∝ φ/f E ∝ 1/(φf) E ∝ f/φ E ∝ φf E ∝ φ/f E ∝ 1/(φf) E ∝ f/φ E ∝ φf ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When two DC series motors are connected in parallel, the resultant speed is less than normal speed. zero. more than normal speed. normal speed. less than normal speed. zero. more than normal speed. normal speed. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a dc machine, the demagnetizing effect of armature reaction is due to uneven air-gap length magnetic saturation in half of the field pole component of armature mmf along field axis non-sinusoidal nature of armature mmf uneven air-gap length magnetic saturation in half of the field pole component of armature mmf along field axis non-sinusoidal nature of armature mmf ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In large sized DC machines the compensating windings are provided to reduce eddy current losses by providing local short circuits. None of these compensate for the decrease in speed due to increase of load. neutralize voltage induced in coil due to fluctuation of l reduce eddy current losses by providing local short circuits. None of these compensate for the decrease in speed due to increase of load. neutralize voltage induced in coil due to fluctuation of l ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines On switching a DC motor to DC supply mains, it is found to rotate in the direction opposite to that for which it is designed. The DC motor is have an equal number of electrons and protons. Differentical compound. Cummulative compound. Series shunt. have an equal number of electrons and protons. Differentical compound. Cummulative compound. Series shunt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A cumulatively compounded dc motor delivers rated load power at rated speed. If the series field is short-circuited, then Ia remains constant but ωm increase both armature current Ia and speed ωm increase Ia increases and ωm decreses both decrese Ia remains constant but ωm increase both armature current Ia and speed ωm increase Ia increases and ωm decreses both decrese ANSWER DOWNLOAD EXAMIANS APP
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