Ray Optics

JEE Main level, single correct, medium

103 of 295

Question 103 of 295

The difference of speed of light in the two media AA and B(vA−vB)B\left({v}_{A}-{v}_{B}\right) is 2.6×107ms−12.6\times {10}^{7}m{s}^{-1}. If the refractive index of medium BB is 1.471.47, then the ratio of refractive index of medium BB to medium AA is: (Given : speed of light in vacuum c=3×108ms−1c=3\times {10}^{8}{ms}^{-1})

Show answer and solution

Answer: (C) 1.131.13

The speed of light in the medium BB will be, vB=cμB{v}_{B}=\dfrac{c}{{\mu }_{B}}
The speed of light in the medium AA will be, vA=cμA{v}_{A}=\dfrac{c}{{\mu }_{A}}.
Now,
vA−vB=c(1μA−1μB)⇒2.6×107=3×108×(1μA−11.47)⇒μA=1.13{v}_{A}-{v}_{B}=c\left(\dfrac{1}{{\mu }_{A}}-\dfrac{1}{{\mu }_{B}}\right) \Rightarrow 2.6\times {10}^{7}=3\times {10}^{8}\times \left(\dfrac{1}{{\mu }_{A}}-\dfrac{1}{1.47}\right) \Rightarrow {\mu }_{A}=1.13

JEE Main question paper PDF

Open a shift to read the full paper on this page, or download it.

JEE Main 2025 Apr 2 Shift 1 question paper

Open Download PDF

Opening paper…

Explain it as a whiteboard videoStep-by-step, in Hinglish or English. Your first video needs no login.Solved it on paper but got it wrong?Upload a photo of your working. Mistake Doctor marks the exact line that broke.
See it move: Lens ray diagram simulationDrag the sliders and watch the numbers in this question change.Revise Ray Optics firstFormula sheet, solved examples and the traps students fall into.

More Physics practice

JEE Main Physics practice question on Ray Optics (Refraction of light from plane surface), with the answer and a step-by-step solution. Scan a question from your own book or paper to get a whiteboard video.