JEE Main 2021 · PhysicsNumerical answerNumerical valueMediumMulti-step

JEE Main 17 March 2021, Shift 2, Physics Q29

Question 29 of 90 in this shift, Physics question 29 of 30, Section B.

A particle of mass m moves in a circular orbit in a central potential field

\mathrm{U(r)=U_0r^4}

. If Bohr's quantization conditions are applied, radii of possible orbitals

\mathrm{r_n}

vary with

\mathrm{n}^{\frac{1}{\alpha}}

, where

\alpha

is ____________.

Official answer

NTA final key.

Chapter: Atoms
Topic: Bohr's Atomic Model
Idea tested: Angular Momentum Quantization

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