Electrical Machines The armature mmf in a dc machine is 1. stationary with respect to field poles 2. stationary with respect to armature 3. rotating with respect to field poles 4. rotating with respect to armature From these, the correct answer is 1, 4 2, 4 1, 3 2, 3 1, 4 2, 4 1, 3 2, 3 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 volt dc motor has an armature winding resistance of 0.5 ohm. Calculate the emf induced by the motor if the full load armature current is 23 ampere. 218.5 volt. None of these. 120 volt. 220.4 volt. 218.5 volt. None of these. 120 volt. 220.4 volt. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The field system of an alternator is usually excited 250 / 250 V DC. 110 / 220 V AC. 3 - Φ, 50 Hz and 400 V. 230 V AC. 250 / 250 V DC. 110 / 220 V AC. 3 - Φ, 50 Hz and 400 V. 230 V AC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines If a transformer has turns ratio K, the primary and secondary current are I1 and I2 respectively and magnetizing current and core loss component of no load current Iμ and Iw respectively, then I1 = KI2 + Iμ. I1 = KI2. I1 = KI2 + Iw + Iμ.ok I1 = KI2 + Iw. I1 = KI2 + Iμ. I1 = KI2. I1 = KI2 + Iw + Iμ.ok I1 = KI2 + Iw. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An inverted V curve of synchronous motor shows variation of power factor and DC excitation at constant load. supply voltage and field current at constant excitation. supply voltage and excitation current at constant load. power factor and supply voltage during hunting. power factor and DC excitation at constant load. supply voltage and field current at constant excitation. supply voltage and excitation current at constant load. power factor and supply voltage during hunting. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For small value armature current Ia the torque developed by a DC series motor is proportional to Ia2. √Ia. Ia. 1/Ia. Ia2. √Ia. Ia. 1/Ia. ANSWER DOWNLOAD EXAMIANS APP