JEE Main 2021ChemistryStructure of AtomEasyNumerical

JEE Main 2021 — Structure of Atom Question with Solution

JEE Main 2021 (26 Feb Shift 2)

Question

A ball weighing 10 g is moving with a velocity of 90 m s-1. If the uncertainty in its velocity is 5%, then the uncertainty in its position is _  ×10-33 m. (Rounded off to the nearest integer)

[Given: h=6.63×10-34 Js]

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Correct answer
1

Step-by-step explanation

Δv=90×5100

=4.5 m s-1

Δv.Δx=h4πm

Δx=h4πm·Δv

=6.63×10-344×3.14×0.01×4.5

=1.17×10-33

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About this question

This is a previous-year question from JEE Main 2021, 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.