JEE Main 2014PhysicsAtomic PhysicsMediumMCQ

JEE Main 2014 — Atomic Physics Question with Solution

JEE Main 2014 (06 Apr)

Question

Hydrogen (1H1), Deuterium (1H2), singly ionised Helium (2He4)+ and doubly ionised lithium (3Li6)++ all have one electron around the nucleus. Consider an electron transition from n=2 to n=1. If the wave lengths of emitted radiation are λ 1 ,  λ 2 ,  λ 3  and λ 4  respectively then approximately which one of the following is correct ?

Choose an option

Show full solutionCorrect option: C
Correct answer
C λ 1 = λ 2 = 4 λ 3 = 9 λ 4

Step-by-step explanation

For radiation, we know that

1λ=RZ21n12-1n22

∴    λ ∝ 1 Z 2

λ 1 ∝ 1 1

λ 2 ∝ 1 1

λ 3 ∝ 1 4

λ 4 ∝ 1 9

∴    λ 1 = λ 2 = 4 λ 3 = 9 λ 4

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About this question

This is a previous-year question from JEE Main 2014, covering the Atomic Physics chapter of Physics. 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.