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Friday, 9 October

NEET UG 2018 · Physics · Question 12

NEET 2018 Physics, question 12

Question 12 of the NEET 2018 paper (code AA) is a Physics question from Dual Nature of Radiation and Matter. Its idea, de Broglie Wavelength of Particles, was asked 4 times, in 2017, 2018, 2022 and 2024, across NEET 2017–2026. The CBSE official answer key gives option 3.

Updated 2026-10-08

Q12 · Physics

An electron of mass m with an initial velocity V⃗=V0i^\vec{V} = V_0\hat{i} (V0>0V_0 > 0) enters an electric field E⃗=−E0i^\vec{E} = -E_0\hat{i} (E0E_0 = constant > 0) at t = 0. If λ0\lambda_0 is its de-Broglie wavelength initially, then its de-Broglie wavelength at time t is

  1. 1λ0t\lambda_0 t
  2. 2λ0(1+eE0mV0t)\lambda_0\left(1 + \frac{eE_0}{mV_0}t\right)
  3. 3λ0(1+eE0mV0t)\frac{\lambda_0}{\left(1 + \frac{eE_0}{mV_0}t\right)}Official answer
  4. 4λ0\lambda_0

Official answer: option 3 · CBSE official answer key

Same idea

de Broglie Wavelength of Particles, in other papers

NEET asked this idea 4 times, in 2017, 2018, 2022 and 2024. The other 3 questions below.

  • 2024 Q34The graph which shows the variation of (1λ2)\left(\frac{1}{\lambda^2}\right) and its kinetic energy, EE is (where λ\lambda is de Broglie…Figure-based · Medium
  • 2022 Q30The graph which shows the variation of the de Broglie wavelength (λ\lambda) of a particle and its associated momentum (p) is :Figure-based · Easy
  • 2017 Q6The de-Broglie wavelength of a neutron in thermal equilibrium with heavy water at a temperature T (Kelvin) and mass m, is :One-line MCQ · Medium

de Broglie Wavelength of Particles: every question and how it was framed

The chapter

Dual Nature of Radiation and Matter in ten years of NEET

20 questions from 2017–2026, asked in 10 of 10 papers, about 1.9 a paper. Photoelectric Effect alone had 20.

Chapter analysisStudy this chapterPractise this chapter

Dual Nature of Radiation and Matter: questions per paper

0241’172’181’193’202’212’222’232’242’253’26