JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 9 January 2020, Shift 2, Physics Q19

Question 19 of 75 in this shift, Physics question 19 of 25, Section A.

The energy required to ionise a hydrogen like ion in its ground state is 9 Rydbergs. What is the wavelength of the radiation emitted when the electron in this ion jumps from the second excited state to the ground state ?

(1)11.4 nmOfficial answer
(2)24.2 nm
(3)8.6 nm
(4)35.8 nm

Official answer

Option 1

NTA final key (Jan 2020).

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Identifying Atomic Number from Spectra

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.