JEE Main 2024 · PhysicsNumerical answerNumerical valueHardMulti-step

JEE Main 4 April 2024, Shift 1, Physics Q60

Question 60 of 90 in this shift, Physics question 30 of 30, Section B.

A hydrogen atom changes its state from n = 3 to n = 2. Due to recoil, the percentage change in the wave length of emitted light is approximately

1 \times 10^{-n}

. The value of n is ________. [Given Rhc = 13.6 eV, hc = 1242 eV nm,

h = 6.6 \times 10^{-34}

J s, mass of the hydrogenatom =

1.6 \times 10^{-27}

kg]

Official answer

NTA final key.

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Atom Recoil During Emission

Same idea in other shifts

Asked 3× in all

29 Jan 2024, Shift 1 · Q60When a hydrogen atom going from $n$ =2 to $n$ =1 emits a photon, its recoil speed is $\frac{x}{5}\ m/s$ . Where $x$ = ______. (Use, mass of…MediumNumerical value
26 Feb 2021, Shift 2 · Q14The recoil speed of a hydrogen atom after it emits a photon in going from n = 5 state to n = 1 state will be :MediumSingle correct

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.