Electrical Machines Oil is provided in an oil filled transformer for both cooling and insulation. insulating. lubrication. cooling. both cooling and insulation. insulating. lubrication. cooling. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines To have sparkless commutation, the armature reaction effect in a DC machine is neutralized by compensating winding and commutating poles. fixing the brush axis inline with the pole axis. increasing field excitation. shifting the brush axis from GNA to MNA. compensating winding and commutating poles. fixing the brush axis inline with the pole axis. increasing field excitation. shifting the brush axis from GNA to MNA. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If starter is not used with large DC motor for starting, it will all of above. provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. all of above. provide execessive voltage drop in line. draw a starting current many times its rated full load current. damage the armature and commutator. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What type of dielectric material is used in capacitors used for fans and for power factor correction? Glass. Vacuum. Mica. Oil impregnated paper. Glass. Vacuum. Mica. Oil impregnated paper. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. decreased. remains same. kept constant to certain value. increased. decreased. remains same. kept constant to certain value. increased. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. PN / 2 Hz. 120N / P Hz. 120 / PN Hz. 120P / N Hz. ANSWER DOWNLOAD EXAMIANS APP
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