JEE Main 2024 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 1 February 2024, Shift 2, Physics Q46

Question 46 of 90 in this shift, Physics question 16 of 30, Section A.

Monochromatic light of frequency

6\times10^{14}

Hz is produced by a laser. The power emitted is

2\times10^{-3}

W. How many photons per second on an average, are emitted by the source ? (Given

h = 6.63\times10^{-34}

Js)

(1) $5\times10^{15}$ Official answer
(2) $7\times10^{16}$
(3) $6\times10^{15}$
(4) $9\times10^{18}$

Official answer

Option 1

NTA final key.

Chapter: Dual Nature of Radiation and Matter
Topic: Photoelectric Effect
Idea tested: Photon Flux and Beam Power

Same idea in other shifts

Asked 7× 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 108 of the 174 JEE Main shifts held from 2017 to 2026.