JEE Main 2021 · PhysicsMultiple choiceSingle correctEasyApplication

JEE Main 22 July 2021, Shift 2, Physics Q10

Question 10 of 90 in this shift, Physics question 10 of 30, Section A.

An electron of mass

\mathrm{m_e}

and a proton of mass

\mathrm{m_p}

are accelerated through the same potential difference. The ratio of the de-Broglie wavelength associated with the electron to that with the proton is :

(1) $1$
(2) $\frac{m_p}{m_e}$
(3) $\frac{m_e}{m_p}$
(4) $\sqrt{\frac{m_p}{m_e}}$ Official answer

Official answer

Option 4

NTA final key.

Chapter: Dual Nature of Radiation and Matter
Topic: Matter Waves
Idea tested: Wavelength from Accelerating Potential

Same idea in other shifts

Asked 5× in all

6 Apr 2026, Shift 2 · Q47The de Broglie wavelength for an electron accelerated through the potential difference of $V_1$ volt is $\lambda_1$ . When the potential…EasyNumerical value
12 Apr 2023, Shift 1 · Q47A proton and an $\alpha$ -particle are accelerated from rest by 2 V and 4 V potentials, respectively. The ratio of their de-Broglie…MediumSingle correct
28 Jul 2022, Shift 1 · Q47The equation $\lambda=\frac{1.227}{x}$ nm can be used to find the de-Brogli wavelength of an electron. In this equation $x$ stands for :…EasySingle correct
30 Jul 2022, Shift 2 · Q19The de Broglie wavelength associated with an electron, accelerated through a potential difference of 15056 V, is: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.