Electrical Machines Which DC motor will have least percentage increase of input current, for the same percentage increase in the torque DC Shunt Motor Compound Wound DC Motor Separately Excited DC Motor DC Series Motor DC Shunt Motor Compound Wound DC Motor Separately Excited DC Motor DC Series Motor ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following factors improve commutation in a dc machine ? 1. High contact resistance of brushes 2. High inductance of the coils undergoing commutation 3. Shifting of brushes in the direction of rotation for a generator and in the opposite direction For a motor 4. Narrow width for the commutation bars Select the correct answer using the codes given below : Codes : 1 and 3 2, 3 and 4 1, 2, and 3 1, 2 and 4 1 and 3 2, 3 and 4 1, 2, and 3 1, 2 and 4 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 I1 = I2 I1 < I2 None of these I1 > I2 I1 = I2 I1 < I2 None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines For a single phase capacitor start induction motor which of the following is valid? Rotation can be changed by interchanging supply terminals. Rotation can be changed by reversing main winding terminals. Direction of rotation cannot be changed. None of these. Rotation can be changed by interchanging supply terminals. Rotation can be changed by reversing main winding terminals. Direction of rotation cannot be changed. None of these. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following relation is correct? Xd = Xq. None of these Xd > Xq. Xd < Xq. Xd = Xq. None of these Xd > Xq. Xd < Xq. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines A Shunt generator running at 1000 rpm has generated emf of 100 V. If the speed increases to 1200 rpm, the generated emf will be nearly 120 V 140 V 240 V 175 V 120 V 140 V 240 V 175 V ANSWER DOWNLOAD EXAMIANS APP