JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyCalculation

JEE Main 25 February 2021, Shift 2, Physics Q15

Question 15 of 90 in this shift, Physics question 15 of 30, Section A.

An electron of mass

m_e

and a proton of mass

m_p = 1836\ m_e

are moving with the same speed. The ratio of their de Broglie wavelength

\frac{\lambda_{electron}}{\lambda_{proton}}

will be :

(1)1
(2)1836Official answer
(3) $\frac{1}{1836}$
(4)918

Official answer

Option 2

NTA final key.

Chapter: Dual Nature of Radiation and Matter
Topic: Matter Waves
Idea tested: Wavelength Ratios of Different Particles

Same idea in other shifts

Asked 15× in all

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1 Feb 2024, Shift 1 · Q46The de Broglie wavelengths of a proton and an $\alpha$ particle are $\lambda$ and $2\lambda$ respectively. The ratio of the velocities of…EasySingle correct
11 Apr 2023, Shift 2 · Q45The ratio of the de-Broglie wavelengths of proton and electron having same Kinetic energy : (Assume $\mathrm{m_p = m_e\times1849}$ )EasySingle correct
25 Jul 2022, Shift 2 · Q37The ratio of wavelengths of proton and deuteron accelerated by potential $\mathrm{V_p}$ and $\mathrm{V_d}$ is $1:\sqrt{2}$ . Then, the…EasySingle correct
25 Jun 2022, Shift 2 · Q46A proton, a neutron, an electron and an $\alpha$ -particle have same energy. If $\lambda_p, \lambda_n, \lambda_e$ and $\lambda_\alpha$ are…MediumSingle correct
27 Jun 2022, Shift 1 · Q43An $\alpha$ particle and a carbon 12 atom has same kinetic energy K. The ratio of their de-Broglie wavelengths…EasySingle correct
31 Aug 2021, Shift 1 · Q4A moving proton and electron have the same de-Broglie wavelength. If K and P denote the K.E. and momentum respectively. Then choose the…EasySingle 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 108 of the 174 JEE Main shifts held from 2017 to 2026.