JEE Main 2023 — Physics Optics
A convex lens of refractive index 1.5 and focal length 18cm in air is immersed in water. The change in focal length of the lens will be_____cm.
(Given refractive index of water=34)
Held on 24 Jan 2023 · Verified 6 Jul 2026.
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In a microscope of tube length 10 cm two convex lenses are arranged with focal length of 2 cm and 5 cm. Total magnification obtained with this system for normal adjustment is $(5)^{k}$. The value of $k$ is $\_\_\_\_$.
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