JEE Main 2021 — Structure Of Atom Question with Solution
From: JEE Main 2021 (Online) 16th March Morning Shift
Question
When light of wavelength 248 nm falls on a metal of threshold energy 3.0 eV, the de-Broglie wavelength of emitted electrons is _______. (Round off to the Nearest Integer).
[ Use : = 1.73, h = 6.63 1034 Js
me = 9.1 1031 kg; c = 3.0 108 ms1; 1eV = 1.6 1019 J]
[ Use : = 1.73, h = 6.63 1034 Js
me = 9.1 1031 kg; c = 3.0 108 ms1; 1eV = 1.6 1019 J]
Enter your answer
Show full solutionCorrect answer: 8.7
Correct answer
8.7
Step-by-step explanation
= 248 109 m
w0 = 3 1.6 1019 J
E = w0 + K.E.
= 3.2 1019 J
p =
p =
p = 7.63 1025
= 8.7 1010 = 8.7 9
w0 = 3 1.6 1019 J
E = w0 + K.E.
= 3.2 1019 J
p =
p =
p = 7.63 1025
= 8.7 1010 = 8.7 9
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