Electrical Machines No load primary current in a transformer leads the applied voltage by exactly 90Â& lags behind applied voltage somewhat less than 90à lags behind applied voltage by exactly 90Â&am leads the applied voltage somewhat less than 90Ã& leads the applied voltage by exactly 90Â& lags behind applied voltage somewhat less than 90à lags behind applied voltage by exactly 90Â&am leads the applied voltage somewhat less than 90Ã& ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a certain transformer is increased by 50% and the frequency is reduced by 50%, the maximum flux density will (assuming that the magnetic circuit remains unsaturated) changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value changes to 1.5 times the original value remain the same as the original changes to three times the original value changes to 0.5 times the original value ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc series motor driving and electric train faces a constant power load. It is running at rated speed and rated voltage. If the speed has to be brought down to 0.25 p.u. the supply voltage has to be approximately brought down to 0.125 p.u 0.75 p.u 0.5 p.u 0.25 p.u 0.125 p.u 0.75 p.u 0.5 p.u 0.25 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage to a dc machine is 230 V, then the back emf, for maximum power developed, is 200 V 115 V 230 V 460 V 200 V 115 V 230 V 460 V ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The speed of a 3-phase induction motor operating in its stable region decreases with increase in the load torque. remains constant. decreases with decrease in the load torque. increases with increase in the load torque. decreases with increase in the load torque. remains constant. decreases with decrease in the load torque. increases with increase in the load torque. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 4 pole 50 Hz induction motor is running at 1470 rpm. What is the slip value? 0.02 0.04 0.2 0.4 0.02 0.04 0.2 0.4 ANSWER DOWNLOAD EXAMIANS APP