Electrical Machines The total core loss of a 400 V, 50 Hz transformer is 2400W, when it is supplied by 200 V, 25 Hz loss is 800W. Calculate eddy current loss and hysteresis loss? 800W, 1600W 1600W, 800W 1400W, 1000W 1000W , 1400W 800W, 1600W 1600W, 800W 1400W, 1000W 1000W , 1400W ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The armature core of a DC machine is laminated to minimise temperature rise hysteresis loss eddy-current loss mechanical loss temperature rise hysteresis loss eddy-current loss mechanical loss ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC generator sparking between brushes and commutator surface may be due to over commutation. any of the above. too rapid reversal of current. under commutation. over commutation. any of the above. too rapid reversal of current. under commutation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A commutator in DC machines can 1. provide half-wave rectification 2. Provide full-wave rectification 3. convert ac to dc 4. Convert dc to ac 5. provide controlled full-wave rectification From these, the correct answer is 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 2, 3, 4 1, 2, 3 2, 3 ,5 2, 3, 4, 5 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 2 pole synchronous machine is operating at 3000 rpm. Find the relation between electrical angular momentum (ωe) and mechanical angular momentum (ωm) ? ωe = 4*ωm ωe = ωm ωe = 2*ωm ωe = 1/2*ωm ωe = 4*ωm ωe = ωm ωe = 2*ωm ωe = 1/2*ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the shunt resistance component equivalent circuit obtained by no load test of an induction motor representative of ? Copper loss windage and friction loss both 1 and 2 core loss only Copper loss windage and friction loss both 1 and 2 core loss only ANSWER DOWNLOAD EXAMIANS APP
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