JEE Main 2015PhysicsAtomic PhysicsMediumMCQ

JEE Main 2015 — Atomic Physics Question with Solution

JEE Main 2015 (10 Apr Online)

Question

If one were to apply the Bohr model to a particle of mass 'm' and charge 'q' moving in a plane under the influence of a magnetic field 'B', the energy of the charged particle in the nth level will be:

Choose an option

Show full solutionCorrect option: B
Correct answer
BnhqB4πm

Step-by-step explanation

For a charge q moving in a uniform magnetic field B



fm=mv2R 

qVB= mv2R 

⇒           mv2=qVBR

⇒        12 mv2=qVBR2

⇒     Energy=qVBR2      (1)

By Bohr's quantization condition, 

Angular momentum L=nh2π

⇒     mvR=nh2π

⇒     vR=nh2π m       (2)

Put (2) in (1)

⇒     Energy=qB2 nh2 π m

= qB nh4 π m

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Atomic Physics chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2015, covering the Atomic Physics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.