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Physics

Wave Optics

Huygens' principle, interference through Young's double slit experiment, single slit diffraction, and polarisation make up wave optics. NEET repeats a few numerical patterns: fringe width changes, path difference conditions, and intensity from polaroids using Malus's law.

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

Wave Optics 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 Wave Optics, with the answer and the working. Try before you peek.

Question 1 · NEET 2026

In Young's double slit experiment, using monochromatic light of wavelength λ\lambda, the intensity of light at a point on the screen where the path difference is λ\lambda, is KK units. The intensity of light at a point where the path difference is λ3\dfrac{\lambda}{3} will be
  1. A.K4\dfrac{K}{4}
  2. B.KK
  3. C.2K2K
  4. D.K2\dfrac{K}{2}
Answer and explanation

Answer: A

The interference intensity follows I=I0cos⁡2(Δϕ2)I = I_0\cos^2\left(\dfrac{\Delta\phi}{2}\right). A path difference of λ\lambda gives Δϕ=2π\Delta\phi = 2\pi, so I=I0=KI = I_0 = K, i.e. I0=KI_0 = K. For a path difference λ/3\lambda/3, Δϕ=2π3\Delta\phi = \dfrac{2\pi}{3}, giving I=I0cos⁡2(π3)=I04=K4I = I_0\cos^2\left(\dfrac{\pi}{3}\right) = \dfrac{I_0}{4} = \dfrac{K}{4} (option A). The other choices ignore the cos⁡2\cos^2 dependence on phase.

How to practise Wave Optics

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 Wave Optics have in NEET 2026?

Wave Optics 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 Wave Optics 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 Wave Optics 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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