Question:
What is the focal length of a double concave lens kept in air with two spherical surfaces of radii \(R_1=30 \ cm,\ R_2=60\ cm\) and refractive index of glass is \(n=1.5\)?
What is the focal length of a double concave lens kept in air with two spherical surfaces of radii \(R_1=30 \ cm,\ R_2=60\ cm\) and refractive index of glass is \(n=1.5\)?
Updated On: Apr 29, 2024
- 40 cm
- -40 cm
- 50 cm
- -50 cm
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The Correct Option is B
Solution and Explanation
The correct option is (B): -40 cm.
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