The image of an object placed in air formed by a convex refracting surface is at a distance of 10 m behind the surface. The image is real and is at ${{{2^{rd}}} \over 3}$ of the distance of the object from the surface. The wavelength of light inside the surface is ${2 \over 3}$ times the wavelength in air. The radius of the curved surface is ${x \over {13}}$ m. The value of 'x' is ___________.
Answer (integer)
30
Solution
${{{\mu _2}} \over v} - {{{\mu _1}} \over u} = {{{\mu _2} - {\mu _1}} \over R}$<br><br>${\mu _1} = 1$, ${\mu _2} = 1.5$<br><br>${{1.5} \over { + 10}} - {1 \over { - 15}} = {{1.5 - 1} \over { + R}}$<br><br>$R = {{30} \over {13}}$ m
About this question
Subject: Physics · Chapter: Optics · Topic: Refraction and Snell's Law
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