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Friday, 9 October

NEET UG 2020 · Physics · Question 168

NEET 2020 Physics, question 168

Question 168 of the NEET 2020 paper (code E1) is a Physics question from Wave Optics. Its idea, Angular Radius of Airy Disk, was asked only this once in NEET 2017–2026. The NTA final answer key gives option 1.

Updated 2026-10-08

Q168 · Physics

Assume that light of wavelength 600 nm is coming from a star. The limit of resolution of telescope whose objective has a diameter of 2 m is :

  1. 13.66×10−73.66\times10^{-7} radOfficial answer
  2. 21.83×10−71.83\times10^{-7} rad
  3. 37.32×10−77.32\times10^{-7} rad
  4. 46.00×10−76.00\times10^{-7} rad

Official answer: option 1 · NTA final answer key

Same idea

The only question on Angular Radius of Airy Disk

No other NEET paper from 2017–2026 tested this exact idea.

Angular Radius of Airy Disk: every question and how it was framed

The chapter

Wave Optics in ten years of NEET

15 questions from 2017–2026, asked in 8 of 10 papers, about 1.5 a paper. Single Slit Diffraction alone had 8.

Chapter analysisStudy this chapterPractise this chapter

Wave Optics: questions per paper

0243’172’181’193’200’211’221’232’242’250’26