JEE Main 2023 · PhysicsNumerical answerNumerical valueEasyCalculation

JEE Main 13 April 2023, Shift 1, Physics Q51

Question 51 of 90 in this shift, Physics question 21 of 30, Section B.

The radius of

2^{\text{nd}}

orbit of

\mathrm{He^+}

of Bohr's model is

r_1

and that of fourth orbit of

\mathrm{Be^{3+}}

is represented as

r_2

. Now the ratio

\frac{r_2}{r_1}

x : 1

. The value of

x

is ____________

Official answer

NTA final key.

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Bohr Orbit Radius

Same idea in other shifts

Asked 6× in all

2 Apr 2025, Shift 2 · Q40Assuming the validity of Bohr's atomic model for hydrogen like ions the radius of $\mathrm{Li^{++}}$ ion in its ground state is given by…EasySingle correct
27 Jan 2024, Shift 1 · Q47The radius of third stationary orbit of electron for Bohr's atom is R. The radius of fourth stationary orbit will be :EasySingle correct
6 Apr 2023, Shift 1 · Q53The radius of fifth orbit of the $\mathrm{Li^{++}}$ is ____________ $\times10^{-12}$ m. Take: radius of hydrogen atom = 0.51 ÅEasyNumerical value
6 Apr 2023, Shift 2 · Q56Experimentally it is found that 12.8 eV energy is required to separate a hydrogen atom into a proton and an electron. So the orbital…MediumNumerical value
30 Jul 2022, Shift 2 · Q17Using Boh'r model of quantization of angular momentum the relation between the radius 'r' of the n $^{\mathrm{th}}$ allowed orbit of…EasySingle 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.