JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 25 July 2021, Shift 1, Physics Q6

Question 6 of 90 in this shift, Physics question 6 of 30, Section A.

What should be the order of arrangement of de-Broglie wavelength of electron (

\lambda_e

), an

\alpha

-particle (

\lambda_\alpha

) and proton (

\lambda_p

) given that all have the same kinetic energy ?

(1) $\lambda_e<\lambda_p<\lambda_\alpha$
(2) $\lambda_e=\lambda_p=\lambda_\alpha$
(3) $\lambda_e>\lambda_p>\lambda_\alpha$ Official answer
(4) $\lambda_e=\lambda_p>\lambda_\alpha$

Official answer

Option 3

NTA final key.

Chapter: Dual Nature of Radiation and Matter
Topic: Matter Waves
Idea tested: Wavelength from Kinetic Energy

Same idea in other shifts

Asked 4× in all

8 Apr 2024, Shift 1 · Q44A proton and an electron are associated with same de-Broglie wavelength. The ratio of their kinetic energies is: (Assume…EasySingle correct
9 Apr 2024, Shift 1 · Q46A proton, an electron and an alpha particle have the same energies. Their de-Broglie wavelengths will be compared as :EasySingle correct
6 Apr 2023, Shift 1 · Q35The kinetic energy of an electron, $\alpha$ -particle and a proton are given as 4 K, 2 K and K respectively. The de-Broglie wavelength…MediumSingle correct

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.