JEE Main 2021 · ChemistryNumerical answerNumerical valueEasyCalculation

JEE Main 4 August 2021, Shift 1, Chemistry Q52

Question 52 of 90 in this shift, Chemistry question 22 of 30, Section B.

The wavelength of a tennis ball of mass 57 g travelling at 80 km h

^{-1}

is ________

\times 10^{-34}

m. (Nearest integer) [Use : h =

6.6 \times 10^{-34}

J s]

Official answer

NTA final key.

Chapter: Structure of Atom
Topic: Matter Waves
Idea tested: Basic Wavelength-Momentum Relation

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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.