From the circuit diagram,
$\begin{aligned}
& 5 \mathrm{i}=\frac{20}{400}=\frac{1}{20} \mathrm{A} \
& \therefore \mathrm{i}=\frac{1}{100} \mathrm{A}=10 \mathrm{~mA}=\text { Load current }
\end{aligned}$
Also, VL=5 V
∴RL=10×10−35Ω=500Ω
A zener diode with 5 V zener voltage is used to regulate an unregulated dc voltage input of 25 V. For a 400Ω resistor connected in series, the zener current is found to be 4 times load current. The load current (IL) and load resistance (RL) are :
Held on 2 Apr 2025 · Verified 6 Jul 2026.
IL=20 mA;RL=250Ω
IL=10 A;RL=0.5Ω
IL=0.02 mA;RL=250Ω
IL=10 mA;RL=500Ω
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