Electrical Machines What is the frequency of a alternator, if P = number of poles and N = revolution made per second? PN / 2 Hz. 120 / PN Hz. 120N / P Hz. 120P / N Hz. PN / 2 Hz. 120 / PN Hz. 120N / P Hz. 120P / N Hz. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of a DC machine is laminated to minimise mechanical loss temperature rise eddy-current loss hysteresis loss mechanical loss temperature rise eddy-current loss hysteresis loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc motor with armature resistance of 0.5 ohms connected directly to a 230 Volt supply. If the armature is stationary then the current flowing through armature is 340 A. 460 A. 250 A. 570 A. 340 A. 460 A. 250 A. 570 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a given torque, reducing divertor resistance of a DC series motor 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 The self induced emf in the coil undergoing commutation is called the statically induced voltage. dynamically induced voltage. reactance voltage. None of these statically induced voltage. dynamically induced voltage. reactance voltage. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator, the armature reaction results in demagnetization of leading & magnetization of trailing pole tip. magnetization of inter poles. demagnetization of centers of poles. magnetization of leading and demagnetization of trailing pole tip. demagnetization of leading & magnetization of trailing pole tip. magnetization of inter poles. demagnetization of centers of poles. magnetization of leading and demagnetization of trailing pole tip. ANSWER DOWNLOAD EXAMIANS APP