The zener diode has a $V_{z}=30 \mathrm{~V}$. The current passing through the diode for the followin

Question

The zener diode has a $V_{z}=30 \mathrm{~V}$. The current passing through the diode for the following circuit is ________ mA .\

Professor PC Thomas Classes · Answer

(9) : Voltage across $4 \mathrm{k} \Omega=90-30$
$$
=60 \mathrm{~V}
$$
Total current $I=\frac{60}{4 	imes 10^{3}}=15 	imes 10^{-3} \mathrm{~A}$\
So, current in $5 \mathrm{k} \Omega$,
$$
I^{\prime}=\frac{30}{5 	imes 10^{3}}=6 	imes 10^{-3} \mathrm{~A}$$
Current in diode $I^{\prime \prime}=I-I^{\prime}$
$=(15-6) 	imes 10^{-3}=9 \mathrm{~mA}$