Electrical Machines Find the number of poles required, when the frequency is 50Hz and speed of the motor is 500 rpm? 12 5 24 10 12 5 24 10 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Short circuit test is performed on a transformer with a certain impressed voltage at rated frequency. If the short circuit test is now performed with the same magnitude of impressed voltage, but at frequency higher than the rated frequency then The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. The magnitude will both increase. The magnitude of current will decrease but the power factor will increase. The magnetude of current will increase, but power factor will decrease. The magnitude of circuit as well as the power factor will decrease. The magnitude will both increase. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When applied rated voltage per phase is reduce to one half, the starting torque of three phase squirrel cage induction motor becomes twice the initial value 1/4 of the intial value 1/2 of the initial value 4 time the initial value twice the initial value 1/4 of the intial value 1/2 of the initial value 4 time the initial value ANSWER DOWNLOAD EXAMIANS APP
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 / 2. sf. f / s. s2. sf / 2. sf. f / s. s2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Flux density under leading pole tips in case of generator will either increase or decrease None of these decrease increase either increase or decrease None of these decrease increase ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The main disadvantage(s) of the ward-Leonard system is/are all of above. high initial cost. poor overall efficiency. high maintenance cost. all of above. high initial cost. poor overall efficiency. high maintenance cost. ANSWER DOWNLOAD EXAMIANS APP