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An initially parallel cylindrical beam travels in a medium of refractive index μ(I)= 0+ 2 I, where 0 and 2 are positive constants and I is the intensity of the light beam. The intensity of the beam is decreasing with increasing radius. The speed of light in the medium is

the same everywhere in the beam

directly proportional to the intensity I

maximum on the axis of the beam

Ray Optics

JEE Main level, single correct, medium

117 of 295

Question 117 of 295

An initially parallel cylindrical beam travels in a medium of refractive index $\mu(I)=\mu_0+\mu_2 I$ , where $\mu_0$ and $\mu_2$ are positive constants and $\mathrm{I}$ is the intensity of the light beam. The intensity of the beam is decreasing with increasing radius.
The speed of light in the medium is

Show answer and solution

Answer: (A) minimum on the axis of the beam

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JEE Main question paper PDF

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JEE Main 2025 Apr 2 Shift 1 question paper

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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.