Question

Find the currents through the resistances in the circuits shown in figure.

Answer

  1. Since both the diodes are forward biased net resistance = 0

$\text{i}=\frac{2\text{V}}{2\Omega}=1\text{A}$
  1. One of the diodes is forward biased and other is reverse biase.
Thus the resistance of one becomes $\infty.$

$\text{i}=\frac{2}{2+\infty}=0\text{A}$
Both are forward biased.
Thus the resistance is 0.

$\text{i}=\frac{2}{2}=1\text{A}.$
One is forward biased and other is reverse biased.
Thus the current passes through the forward biased diode.

$\therefore\text{i}=\frac{2}{2}=1\text{A}.$

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