Question

The circuit contains two diodes, each with a forward resistance of $50\Omega$ and with infinite reverse resistance. If the battery voltage is $6\text{V}$, the current through the $120\Omega$ resistance is _________ $\text{mA}$.

Answer 1

Clearly, $D_2$ is reverse biased, so current does not flow through $D_2$ and $D_1$ is forward biased.

So, the circuit can be redrawn as,


$\therefore I=\frac{6}{130+120+50}=\frac{6}{300}$

$\Rightarrow I=0.02\text{A}=20\times {10}^{-3}\text{A}=20\text{mA}$