JEE Main 2026 — Wave Optics Question with Solution
JEE Main 2026 (08 April Shift 2)
Question
Some distant star is to be observed by some telescope of diameter of objective lens , at an angular resolution of radian. If the wavelength of light from the star reaching the telescope is nm, the minimum diameter of the objective lens of the telescope is ________ cm. (nearest integer)
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Show full solutionCorrect answer: 203
Correct answer
203
Step-by-step explanation
The angular resolution of a telescope is given by the formula:
where is the wavelength of light and is the diameter of the objective lens.
Given:
rad
m m
Substituting the values into the formula:
m
m
Converting the diameter into centimeters:
cm cm
Rounding to the nearest integer, we get cm.
Answer:
where is the wavelength of light and is the diameter of the objective lens.
Given:
rad
m m
Substituting the values into the formula:
m
m
Converting the diameter into centimeters:
cm cm
Rounding to the nearest integer, we get cm.
Answer:
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This is a previous-year question from JEE Main 2026, covering the Wave Optics chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.