Physics · Atomic Physics

JEE Main 2026 — 6 April, Morning Shift — Question 14

The ratio of momentum of the photons of the 1st1^{\mathrm{st}} and 2nd2^{\mathrm{nd}} line of Balmer series of Hydrogen atoms is α/β\alpha/\beta. The possible values of α\alpha and β\beta are :

  1. Option A:

    27 and 20

  2. Option B:

    3 and 16

  3. Option C:

    5 and 36

  4. Option D:

    20 and 27

    Correct

Answer: D

Step-by-step solution

For Balmer series: 1/λ=R(1/22−1/n2)1/\lambda = R(1/2^2 - 1/n^2). First line (n=3): 1/λ1=R(1/4−1/9)=5R/361/\lambda_1 = R(1/4-1/9)=5R/36. Second line (n=4): 1/λ2=R(1/4−1/16)=3R/161/\lambda_2 = R(1/4-1/16)=3R/16. Momentum p=h/λp = h/\lambda, so p1/p2=λ2/λ1=(16/(3R))/(36/(5R))=(16/3)∗(5/36)=80/108=20/27p_1/p_2 = \lambda_2/\lambda_1 = (16/(3R)) / (36/(5R)) = (16/3)*(5/36)=80/108=20/27. Thus α=20,β=27\alpha=20,\beta=27.

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Physics
Chapter
Atomic Physics
Topic
Hydrogen Spectrum
The ratio of momentum of the photons of the 1 st and 2 nd line of… | JEE Main 2026 PYQ with Solution · DhiX AI