Electrical Machines In a loaded DC motor, if the brushes are given a shift from the interpolar axis in the direction of rotation, then the commutation will deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. deteriorate and the speed falls. improve and the speed falls. improve and the speed rises. deteriorate and the speed rises. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Consider a separately excited DC motor. If the field current is increased while the armature terminal voltage is held constant, then speed of the motor will increase. none of these. remains same. Decrease.d increase. none of these. remains same. Decrease.d 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 0.25 p.u 0.75 p.u 0.125 p.u 0.5 p.u 0.25 p.u 0.75 p.u 0.125 p.u 0.5 p.u ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 3-phase slip ring induction motor is wound for 4 poles on stator and 6 poles on the rotor. When 3-phase balanced voltage source at 50 Hz is applied, it will run at 750rpm 1500 rpm 1000 rpm zero speed 750rpm 1500 rpm 1000 rpm zero speed ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If the applied voltage of a DC motor is 230 V, then back emf, for maximum power developed is 200 V. 230 V. 115 V. 460 V. 200 V. 230 V. 115 V. 460 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following machine will have maximum efficiency? Electrical power generator. Induction motor. Electrical power transformer. DC motor. Electrical power generator. Induction motor. Electrical power transformer. DC motor. ANSWER DOWNLOAD EXAMIANS APP