Electrical Machines In a DC generator, if P be the number of poles and N be the rpm of the rotor, then frequency of magnetic reversals will be PN/60. PN/3000. PN/120. PN/2. PN/60. PN/3000. PN/120. PN/2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing diverter resistance of a DC series motor causes increase in speed but armature currnet remains the same. decrease in speed demanding less armature current. decrease in speed but armature current remains the same. increase in speed demanding more armature current. increase in speed but armature currnet remains the same. decrease in speed demanding less armature current. decrease in speed but armature current remains the same. increase in speed demanding more armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines shape of net flux density is? peaky in nature flat tapped or trapezoidal sine wave saddle shape peaky in nature flat tapped or trapezoidal sine wave saddle shape ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following are variable losses? armature copper loss hysteresis loss shunt field copper loss eddy current loss armature copper loss hysteresis loss shunt field copper loss eddy current loss 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%. 920 RPM 940 RPM 970 RPM 960 RPM 920 RPM 940 RPM 970 RPM 960 RPM ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC Shunt Motor if the load current increases then field flux decreases increases. decreases. remains constant. decreases increases. decreases. remains constant. ANSWER DOWNLOAD EXAMIANS APP
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