JEE Main 2021 — Structure Of Atom Question with Solution
From: JEE Main 2021 (Online) 27th August Evening Shift
Question
The number of photons emitted by a monochromatic (single frequency) infrared range finder of power 1 mW and wavelength of 1000 nm, in 0.1 second is x 1013. The value of x is _____________. (Nearest integer)
(h = 6.63 1034 Js, c = 3.00 108 ms1)
(h = 6.63 1034 Js, c = 3.00 108 ms1)
Enter your answer
Show full solutionCorrect answer: 50.2
Correct answer
50.2
Step-by-step explanation
Energy emitted in 0.1 sec.
= 0.1 sec.
= 104 J
If 'n' photons of = 1000 nm are emitted, then 104 = n
n = 5.02 1014 = 50.2 1013
50 (nearest integer)
= 0.1 sec.
= 104 J
If 'n' photons of = 1000 nm are emitted, then 104 = n
n = 5.02 1014 = 50.2 1013
50 (nearest integer)
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This is a previous-year question from JEE Main 2021, covering the Structure Of Atom chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.