RAY optics

a concavo convex lens of refractive index n2 is placed between 2 media having refractive indices n1 and n3 respectively.find the focal length of lens having radii of curvature of both the surfaces equal to R?

Easy Math Editor

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Comments

In this case one cannot use lens formula because R.I. is not same of both sides of lens. so it will be solved by refraction formula. Also focal length depends on from which sides u r taking the incident light. First take the object at infinity and by refraction formula find the distance of image from 1st surface that will act as a object for second surface and final image's distance will be foacal lenght by definition.

Amit Sharma - 7 years, 1 month ago

Math	Appears as
Remember to wrap math in `\(` ... `\)` or `\[` ... `\]` to ensure proper formatting.
`2 \times 3`	$2 \times 3$
`2^{34}`	$2^{34}$
`a_{i-1}`	$a_{i-1}$
`\frac{2}{3}`	$\frac{2}{3}$
`\sqrt{2}`	$\sqrt{2}$
`\sum_{i=1}^3`	$\sum_{i=1}^3$
`\sin \theta`	$\sin \theta$
`\boxed{123}`	$\boxed{123}$