Electrical Machines A voltmeter gives 120 oscillations per minute when connected to the rotor of an induction motor. The frequency is 50Hz. The slip of the motor is 4% 25% 2% 5% 4% 25% 2% 5% ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A dc shunt generator, when driven without any excitation, showed an open circuit voltage of 12 V. When the field winding was excited, the voltage dropped to zero. It happened because there was no residual magnetism in the field circuit field resistance was higher than critical resistance field winding was wrongly connected there was a break in the armature circuit there was no residual magnetism in the field circuit field resistance was higher than critical resistance field winding was wrongly connected there was a break in the armature circuit 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 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = N1 / N2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Slot wedges in a dc machine is made up of fibre. silicon steel. cast iron. mild steel. fibre. silicon steel. cast iron. mild steel. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In induction motors, there is large decrease in maximum power factor when the dispersion coefficient is ________________. kept constant to certain value. remains same. increased. decreased. kept constant to certain value. remains same. increased. decreased. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A series generator is connected in series to a feeder having 0.5Ω resistance to boost the voltage. The induced voltage is given by Eg = 0.6Ia, Ra = 0.2Ω and Rs = 0.3Ω. Find the voltage boosted by the generator, when delivering 400 Amp? 90 V. 30 V. 60 V. 40 V. 90 V. 30 V. 60 V. 40 V. ANSWER DOWNLOAD EXAMIANS APP