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 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. E1 / E2 = N1kw1 / N2kw2. E1 / E2 = f1kw1 / f2kw2. E1 / E2 = N1 / N2. E1 / E2 = 1. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Find the synchronous reactance of alternators in which a given field current of 200 A on short circuit and a generated emf of 50 V on open circuit. Armature resistance is 0.1 ohm 0.23Ω. 0.25Ω. 0.5Ω. 1Ω. 0.23Ω. 0.25Ω. 0.5Ω. 1Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines As compared to an induction motor, the air gap in a DC motor is less than 50%. more. between 50% and 90%. same. less than 50%. more. between 50% and 90%. same. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For an ideal transformer the winding should have minimum resistance on primary side and maximum resistance on secondary side no ohmic resistance on either side equal resistance on primary and secondary side maximum resistance on primary side and least resistance on secondary side minimum resistance on primary side and maximum resistance on secondary side no ohmic resistance on either side equal resistance on primary and secondary side maximum resistance on primary side and least resistance on secondary side 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? 30 V. 40 V. 90 V. 60 V. 30 V. 40 V. 90 V. 60 V. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Dynamic braking is very effective for separately excited motors. differential compound motors. shunt motors. series motors. separately excited motors. differential compound motors. shunt motors. series motors. ANSWER DOWNLOAD EXAMIANS APP
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