JEE Main 2024 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 6 April 2024, Shift 2, Physics Q55

Question 55 of 90 in this shift, Physics question 25 of 30, Section B.

In Franck-Hertz experiment, the first dip in the current-voltage graph for hydrogen is observed at 10.2 V. The wavelength of light emitted by hydrogen atom when excited to the first excitation level is ________ nm. (Given

hc=1245\ \mathrm{eV\,nm}

e=1.6\times10^{-19}\ \mathrm{C}

Official answer

122

NTA final key.

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Excitation and Ionization Potentials

Same topic in other shifts

All Bohr's Atomic Model questions

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.