JEE Main 2021ChemistryStructure Of AtomQuantum Mechanical Model Of AtommediumNumerical

JEE Main 2021Structure Of Atom Question with Solution

From: JEE Main 2021 (Online) 20th July Evening Shift

Question

The wavelength of electrons accelerated from rest through a potential difference of 40 kV is x 1012 m. The value of x is ___________. (Nearest integer)

Give : Mass of electron = 9.1 1031 kg

Charge on an electron = 1.6 1019 C

Planck's constant = 6.63 1034 Js

Enter your answer

Show full solutionCorrect answer: 6.15
Correct answer
6.15

Step-by-step explanation

Wavelength of electron is given by



Here q = charge on electron, V = potential difference





x = 6

OR



m

Ans. is 6

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About this question

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.