Electrical Machines A transformer has hysteresis loss of 30 W, at 240 V, 60 Hz. The hysteresis loss at 200 V, 50 Hz will be 36 W. 30 W. 25 W. 28 W. 36 W. 30 W. 25 W. 28 W. 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 = 1/2*ωm ωe = 2*ωm ωe = ωm ωe = 4*ωm ωe = 1/2*ωm ωe = 2*ωm ωe = ωm ωe = 4*ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In DC machines, the interpoles are provided to counteract the reactance voltage and the cross-magnetizi to make commutation spark less. both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. to counteract the reactance voltage and the cross-magnetizi to make commutation spark less. both (B) and (C). to counteract demagnetizing effect of armature mmf in commutating zone. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 200 V DC machine supplies 20 A at 200 V as a generator. The armature resistance is 0.2 Ω. If the machine is now operated as a motor at same terminal voltage and current but with the flux increased by 10%, the ratio of motor speed to generator speed is 0.87 1.06 0.96 0.95 0.87 1.06 0.96 0.95 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What is the reason for stationary armature essential in alternators above 5 KVA? All of these Insulation requirement is less. Operating cost is less. Collecting of large current is simple. All of these Insulation requirement is less. Operating cost is less. Collecting of large current is simple. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Cogging of induction motor occurs at low voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are equal. low voltage and when stator and rotor poles are not equal. high voltage and when stator and rotor poles are not equal. low voltage and when stator and rotor poles are equal. high voltage and when stator and rotor poles are equal. low voltage and when stator and rotor poles are not equal. high voltage and when stator and rotor poles are not equal. ANSWER DOWNLOAD EXAMIANS APP