JEE Main 2014PhysicsWave OpticsHardMCQ

JEE Main 2014 — Wave Optics Question with Solution

JEE Main 2014 (09 Apr Online)

Question

Using monochromatic light of wavelength λ , an experimentalist sets up the Young's double slit experiment in three ways as shown.
If she observes that y⁡ = β ′ , the wavelength of light used is :

 

Choose an option

Show full solutionCorrect option: C
Correct answer
C540 nm

Step-by-step explanation

β = λ D d .

∴    β 1 = λ 2 D d.

Now shift = μ - 1 t D d

y= β 1

μ - 1 t D d = λ . 2 D d

λ = μ - 1 t 2 = 1.6 - 1 × 1.8 2

   = 0.6 × 1.8 2 μ m

   = 0.3 × 1.8  μ m

   = 0.54  μ m

  = 540 nm

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About this question

This is a previous-year question from JEE Main 2014, 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.