JEE Main 2026 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 8 April 2026, Shift 2, Physics Q38

Question 38 of 75 in this shift, Physics question 13 of 25, Section A.

A monochromatic source of light operating at 15 kW emits

2.5 \times 10^{22}

photons/s. The region of an electromagnetic spectrum to which the emitted electromagnetic radiation belongs to ________. (Take

h = 6.6 \times 10^{-34}

J.s and

c = 3 \times 10^8

m/s).

(1)Microwave
(2)Infrared
(3)Visible
(4)UltravioletOfficial answer

Official answer

Option 4

NTA final key.

Chapter: Electromagnetic Waves
Topic: Photoelectric Effect
Idea tested: Photon Energy and Momentum

Same idea in other shifts

Asked 3× in all

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