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what is the focal length of a double concave lens
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
\(n=1.5\)
?
TS POLYCET - 2020
TS POLYCET
Updated On:
Apr 17, 2025
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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