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Physics

Dual Nature of Radiation and Matter

The photoelectric effect, Einstein's photoelectric equation, photons, and the de Broglie wavelength of matter are all this compact chapter holds. NEET sticks to predictable numericals: stopping potential, threshold frequency, and de Broglie wavelength of an accelerated particle.

Exam rules change between cycles. Confirm dates, syllabus and pattern against NTA's official site. We are not NTA.

Weightage: what the paper actually did

Dual Nature of Radiation and Matter carried 2 questions in the NEET 2026 paper. One paper is a data point, not a destiny: NTA moves weight between chapters every cycle, which is why the weightage tables deserve care. The stable facts are the paper's shape: 180 questions, 720 marks, +4 right, −1 wrong.

Sample PYQs from this chapter

Real questions NTA asked from Dual Nature of Radiation and Matter, with the answer and the working. Try before you peek.

Question 1 · NEET 2026

For a metal of work function 6.6 eV6.6\ \text{eV}, which of the following wavelengths of incident radiation does not give rise to the photoelectric effect? (Take Planck's constant as 6.6×10−34 J s6.6 \times 10^{-34}\ \text{J s})
  1. A.100 nm
  2. B.150 nm
  3. C.200 nm
  4. D.50 nm
Answer and explanation

Answer: C

Photoemission requires photon energy hcλ≥W0\dfrac{hc}{\lambda} \geq W_0, i.e. wavelength λ≤hcW0\lambda \leq \dfrac{hc}{W_0}. Here hcW0=6.6×10−34×3×1086.6×1.6×10−19≈187.5 nm\dfrac{hc}{W_0} = \dfrac{6.6\times10^{-34}\times3\times10^{8}}{6.6\times1.6\times10^{-19}} \approx 187.5\ \text{nm}. Any wavelength longer than this cannot eject electrons; 200 nm>187.5 nm200\ \text{nm} > 187.5\ \text{nm}, so it produces no photoelectric effect. Why the other options are wrong: - (A) 100 nm < 187.5 nm, so it does cause emission. - (B) 150 nm < 187.5 nm, so it does cause emission. - (D) 50 nm < 187.5 nm, so it does cause emission.

How to practise Dual Nature of Radiation and Matter

Chapter by chapter, against real past-paper questions, on a screen: NEET is computer based from 2027. Read the chapter once, then attempt its PYQs until your accuracy stops climbing, and let the wrong answers tell you which lines to reread. If the chapter keeps refusing to stick, that has its own guide. There is also a free 12-question mock on the exam screen.

Nearby Physics chapters

Questions

How many questions did Dual Nature of Radiation and Matter have in NEET 2026?

Dual Nature of Radiation and Matter carried 2 questions in the NEET 2026 paper. Weightage shifts between cycles, so treat it as a probability, not a promise.

Where can I practise Dual Nature of Radiation and Matter PYQs for NEET?

In the BrainIt app, free until the 2027 exam: its bank holds 50,000 past NTA questions tagged to all 83 chapters, including this one, with accuracy tracked per chapter. A sample question from this chapter is on this page.

Is Dual Nature of Radiation and Matter important for NEET 2027?

It is part of the Physics syllabus the paper draws from, and NEET 2027 is computer based, so practise it on a screen. Your own accuracy in the chapter matters more than any weightage table: a heavy chapter you already score well on needs less time than a light one you keep missing.

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