JEE Mains · Physics · STD 12 - Semicondutor electronics
- JEE Mains 2021
- Hard
- Numerical
A zener diode of power rating \(2\, {W}\) is to be used as a voltage regulator. If the zener diode has a breakdown of \(10 \,{V}\) and it has to regulate voltage fluctuated between \(6\, {V}\) and \(14\, {V}\), the value of \({R}_{{s}}\) for safe operation should be \(....\Omega\)

Pick an option to check your answer.
Answer & Solution
Correct Answer
(B) \(20\)
Step-by-step Solution
Detailed explanation
When unregulated voltage is \(14\, {V}\) voltage across
zener diode must be \(10\, {V}\) So potential difference
across resistor \(\Delta {V}_{{Rs}}=4\, {V}\)
and \({P}_{\text {zener }}=2\, {W}\)
\({VI}=2\)
\({I}=\frac{2}{10}=0.2\, {A}\)
\(\Delta {V}_{{Rs}}={I} {R}_{{s}}\)
\(4 \times 0.2 {R}_{s} \Rightarrow {R}_{5}=\frac{40}{2}=20\, \Omega\)
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