010BE10103092007

12 a) Three resistors, 20 ೧, 90೧ and 10 Q are connected in star. Obtain the (4)
equivalent delta circuit.
b) Use nodal analysis to find currents in the different branches of the circuit (6)

shown below.

20 30 40

12V
5 OQ

13 a) Determine the power dissipated in all the three resistors shown in figure using (6)

mesh analysis.

क „कनं ‏ہے‎ AOV.

0) Determine the values of mesh currents 11 and 12 for the circuit shown in figure. (4)

98 32

14 a) An iron ring 15 cm mean diameter and 10 cm in cross-section is wound with (6)
200 turns of wire. For a flux density of 1 Wb/m2 and a relative permeability of
500, calculate the exciting current, inductance and energy stored when there is
2mm air gap.
b) Write ೩ short note on i) Magneto motive force ii) Reluctance iii) Magnetic flux (4)

iv) Permeability

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