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Saturday, 10 October

JEE Main 2026 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 6 April 2026, Shift 1, Physics Q39

Question 39 of 75 in this shift, Physics question 14 of 25, Section A.

The maximum rated power of the LED is 2 mW and it is used in the circuit with input voltage of 5 V as shown in the figure below. The current through resistance RSR_S is 0.5 mA. The minimum value of the resistance of RSR_S, to ensure that the LED is not damaged is ________ kΩ\Omega.

The figure, in words

Circuit: 5 V battery in series with R_S; then two parallel branches: a 1 kOhm resistor in series with a diode, and a 2 mW LED.
  1. (1)6
  2. (2)2Official answer
  3. (3)4
  4. (4)5

Official answer

Option 2

NTA final key.

Chapter
Semiconductor Electronics: Materials, Devices and Simple Circuits
Topic
No close match in our taxonomy
Idea tested
No close match in our taxonomy

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 42 of the 174 JEE Main shifts held from 2017 to 2026.