JEE Main 2021 — Structure Of Atom Question with Solution
From: JEE Main 2021 (Online) 25th July Morning Shift
Question
A source of monochromatic radiation of wavelength 400 nm provides 1000 J of energy in 10 seconds. When this radiation falls on the surface of sodium, x 1020 electrons are ejected per second. Assume that wavelength 400 nm is sufficient for ejection of electron from the surface of sodium metal. The value of x is ______________. (Nearest integer)
(h = 6.626 1034 Js)
(h = 6.626 1034 Js)
Enter your answer
Show full solutionCorrect answer: 2.01
Correct answer
2.01
Step-by-step explanation
Total energy provided by
Source per second = J
Energy required to eject electron =
=
Number of electrons ejected
=
=
=
=
Source per second = J
Energy required to eject electron =
=
Number of electrons ejected
=
=
=
=
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