JEE Main 2020 · PhysicsMultiple choiceSingle correctMediumCalculation

JEE Main 6 September 2020, Shift 2, Physics Q19

Question 19 of 75 in this shift, Physics question 19 of 25.

Assuming the nitrogen molecule is moving with r.m.s. velocity at 400 K, the de-Broglie wavelength of nitrogen molecule is close to : (Given : nitrogen molecule weight :

4.64\times10^{-26}

kg, Boltzman constant :

1.38\times10^{-23}

J/K, Planck constant :

6.63\times10^{-34}

J.s)

(1)0.20 Å
(2)0.34 Å
(3)0.44 Å
(4)0.24 ÅOfficial answer

Official answer

Option 4

NTA final key (Sep 2020).

Chapter: Dual Nature of Radiation and Matter
Topic: Matter Waves
Idea tested: Wavelength of Gas Molecule via V_rms

Same topic in other shifts

All Matter Waves questions

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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 42 of the 174 JEE Main shifts held from 2017 to 2026.