Electrical Machines If s is the slip and f is the supply frequency of an induction motor, the frequency of rotor current is given by sf. f / s. sf / 2. s2. sf. f / s. sf / 2. s2. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines When a short circuit test on a transformer is performed at 25 V, 50 Hz, the drawn current is I1. If the test is performed by 25 V and 25 Hz and power drawn current is I2, then I1 = I2 None of these I1 < I2 I1 > I2 I1 = I2 None of these I1 < I2 I1 > I2 ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A self-excited shunt generator fails to build up, because 1. the field circuit is open 2. The armature circuit is open 3. the residual magnetism is absent 4. The direction of rotation is wrong From these, the correct answer is 1, 2, 3 and 4 1, 2 and 3 1, 3 3 only 1, 2, 3 and 4 1, 2 and 3 1, 3 3 only ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Star - delta method of starting of motor is not possible in case of single phase induction motor. high torque motor. high speed motor. low horse power motor. single phase induction motor. high torque motor. high speed motor. low horse power motor. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A cumulatively compounded dc motor delivers rated load power at rated speed. If the series field is short-circuited, then both armature current Ia and speed ωm increase Ia increases and ωm decreses Ia remains constant but ωm increase both decrese both armature current Ia and speed ωm increase Ia increases and ωm decreses Ia remains constant but ωm increase both decrese ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines We can apply source transformation to voltage source when a resistance is connected to it in 13 HP. 14 HP. 10 HP. 15 HP. 13 HP. 14 HP. 10 HP. 15 HP. ANSWER DOWNLOAD EXAMIANS APP