Q. When the switch S, in the circuit shown, is closed, then the value of current i will be :

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Solution:

Let voltage at C = xv KCL : $i_1 + i_2 = i$ $\frac{20-x}{2} + \frac{10-x}{4} = \frac{x-0}{2}$ $\Rightarrow x = 10$ and i = 5 amp.

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