Electrical Machines In a DC machine, which of these parameters remain the same whether it runs as a DC motor or a DC generator? Can not be determined. Induced emf. Mechanical power. Armature current. Can not be determined. Induced emf. Mechanical power. Armature current. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A DC Shunt Motor having shunt field resistance of 250 Ω and armature resistance of 0.5 Ω is connected to 250 V supply and load current of 21 A. What is the back emf generated ? 210 V 240 V. 230 V. 150 V. 210 V 240 V. 230 V. 150 V. 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 changes to three times the original value changes to 0.5 times the original value remain the same as the original changes to 1.5 times the original value changes to three times the original value changes to 0.5 times the original value remain the same as the original ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ IM with line frequency f1 and winding factor kw1 and kw2 for stator and rotor respectively the ratio of per phase stator winding emf E1 to per phase rotor winding emf E2 at standstill is given by E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = 1. E1 / E2 = N1 / N2. E1 / E2 = f1kw1 / f2kw2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Regenerative braking is not found in which motor? Induction motor. DC shunt. DC series. DC compound. Induction motor. DC shunt. DC series. DC compound. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a transformer which of the following losses are zero? Rotational loss All of these Iron loss Copper loss Rotational loss All of these Iron loss Copper loss ANSWER DOWNLOAD EXAMIANS APP