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JEE Main 27 August 2021, Shift 2, Physics Q30

Question 30 of 90 in this shift, Physics question 30 of 30, Section B.

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

The figure, in words

Circuit: input terminals on the left (top and bottom, labelled Unregulated voltage); the top rail has resistor R_S in series leading to the right output terminal (labelled Regulated voltage); a zener-diode symbol is connected vertically between the top rail (after R_S) and the bottom rail; the bottom rail runs straight to the right output terminal.

Official answer

NTA final key.

Chapter: Semiconductor Electronics: Materials, Devices and Simple Circuits
Topic: Semiconductor Diodes
Idea tested: Zener Diode Power Dissipation Limits

Same idea in other shifts

Asked 5× in all

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. This question needs a figure we do not reproduce; it is described in words above. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.