JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 26 August 2021, Shift 1, Physics Q5

Question 5 of 90 in this shift, Physics question 5 of 30, Section A.

A particular hydrogen like ion emits radiation of frequency

2.92\times10^{15}

Hz when it makes transition from n=3 to n=1. The frequency in Hz of radiation emitted in transition from n=2 to n=1 will be :

(1) $4.38\times10^{15}$
(2) $6.57\times10^{15}$
(3) $0.44\times10^{15}$
(4) $2.46\times10^{15}$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Rydberg Formula and Spectra

Same idea in other shifts

Asked 10× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.