JEE Main 2022ChemistryStructure of AtomEasyNumerical

JEE Main 2022 — Structure of Atom Question with Solution

JEE Main 2022 (29 Jul Shift 1)

Question

The minimum uncertainty in the speed of an electron in one dimensional region of length 2ao
(Where ao= Bohr radius 52.9pm) is____kms-1 (Nearest integer)  (Given : Mass of electron =9.1×10-31 kg, Planck's constant h=6.63×10-34Js)

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Show full solutionCorrect answer: 548
Correct answer
548

Step-by-step explanation

Heisenberg's uncertainty principle

Δx×Δpx≥h4π

⇒2a0×mΔvx=h4π(minimum)

⇒Δvx=h4π×12a0×1 m

=6.63×10-344×3.14×2×52.9×10-12×9.1×10-31

=548273 ms-1

=548.273 km s-1

=548 km s-1

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About this question

This is a previous-year question from JEE Main 2022, covering the Structure of Atom chapter of Chemistry. 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.