JEE Main 2019PhysicsAtomic PhysicsMediumMCQ

JEE Main 2019 — Atomic Physics Question with Solution

JEE Main 2019 (08 Apr Shift 1)

Question

Radiation coming from transitions n=2 to n=1 of hydrogen atoms fall on He+ ions in n=1 and n=2 states. The possible transition of helium ions as they absorb energy from the radiation is:

Choose an option

Show full solutionCorrect option: B
Correct answer
Bn=2⟶n=4

Step-by-step explanation

E=13.6111-122 eV  ...(1)
For Helium:
E=13.6221n12-1n22 eV ...(2)
From equation (1) and (2)
13.6 34=13.6 4 1n12-1n22
1n12-1n22=316
From option, n1=2 and n2=4  are satisfying the equation.

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About this question

This is a previous-year question from JEE Main 2019, 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.