Electrical Machines The flux involved in the emf equation of a transformer has total value. maximum value. average value. rms value. total value. maximum value. average value. rms value. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of the following DC generators has rising V-I characteristics? Compound. None of them. Series. Shunt. Compound. None of them. Series. Shunt. 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, 2, and 3 1 and 3 1, 2 and 4 2, 3 and 4 1, 2, and 3 1 and 3 1, 2 and 4 2, 3 and 4 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 = 2*ωm ωe = 1/2*ωm ωe = ωm ωe = 4*ωm ωe = 2*ωm ωe = 1/2*ωm ωe = ωm ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines An 8 pole DC generator has 500 armature conductors and useful flux per pole of 0.065 Wb. What will be the emf generated if it is lap connected and runs at 1000 rpm. What must be the speed at which it is driven to produce the same emf if it is wave wound? 541.67V, 200 rpm. 541.67V, 250 rpm. 2166.67V, 230 rpm. 2166.67V, 270 rpm. 541.67V, 200 rpm. 541.67V, 250 rpm. 2166.67V, 230 rpm. 2166.67V, 270 rpm. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Which of following DC motors will have percentage increase of input current for the same percentage increase in torque? Cummulative compound. Shunt. Differntical compound. Series. Cummulative compound. Shunt. Differntical compound. Series. ANSWER DOWNLOAD EXAMIANS APP
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