Question

A $8\text{V}$ Zener diode along with a series resistance $R$ is connected across a $20\text{V}$ supply (as shown in the figure). If the maximum Zener current is $25\text{mA}$, then the minimum value of $R$ will be $\omega$

Answer 1

For maximum current,

$i=\frac{V}{R_{min}}$

$R_{min}=\frac{V}{i}=\frac{12}{25\times {10}^{-3}}=480\Omega$