Electrical Machines The current drawn by a 220 V DC series motor of armature resistance 0.5Ω and back back emf 200 V is 40 A. 400 A. 44 A. 440 A. 40 A. 400 A. 44 A. 440 A. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines What happens if fifth multiples of harmonics is given to induction motor? It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. It will rotates in reverse direction. Fail to start. Either short circuit or open circuit occurs. It will rotates in normal operation. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A 230 V, 50 Hz, 4 pole single phase induction motor is rotating in the clockwise ( forward ) direction at a speed of 1425 rpm. If the rotor resistance at standstill is 7.8 Ω. Then the effective rotor resistance in the backward branch of the equivalent circuit will be 4 Ω. 2 Ω. 8 Ω. 10 Ω. 4 Ω. 2 Ω. 8 Ω. 10 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The mechanical power is developed by a DC motor is maximum when none of above. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. back emf is equal to half of applied voltage. none of above. back emf is equal to applied voltage. back emf is equal to twice of applied voltage. back emf is equal to half of applied voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The result of slip test on a 3-phase, 20 KVA, 400 V, 50 Hz connected salient pole alternator is given below- Phase value: Vmax = 100 V, Vmin = 96 V, Imax = 10 A and I min = 7 A. The direct and quadranature axis reactances are respectively 14.28 and 9.60 Ω. 8.248 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 5.54 Ω. 14.28 and 9.60 Ω. 8.248 and 9.60 Ω. 8.248 and 5.54 Ω. 14.28 and 5.54 Ω. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a DC machine the armature mmf is rotating with respect to field poles. stationary with respect to field poles. rotating with respect to field poles as well as armature. stationary with respect to armature. rotating with respect to field poles. stationary with respect to field poles. rotating with respect to field poles as well as armature. stationary with respect to armature. ANSWER DOWNLOAD EXAMIANS APP