19.A thin glass (refractive index 1.5) lens has optical power of 5D in air. Its optical power in a liquid medium with refractive index 1.6 will be
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![Illustration of the optical set-up used to measure the focal power and... | Download Scientific Diagram Illustration of the optical set-up used to measure the focal power and... | Download Scientific Diagram](https://www.researchgate.net/publication/320392025/figure/fig4/AS:564167968661510@1511519533549/Illustration-of-the-optical-set-up-used-to-measure-the-focal-power-and-quality-of-the.png)
Illustration of the optical set-up used to measure the focal power and... | Download Scientific Diagram
The equivalent optical power of the two-lens system as a function of... | Download Scientific Diagram
![MathType on Twitter: "The focal length for a positive converging lens in air is the distance from the lens to the point where the incident light beam is focused. It can be MathType on Twitter: "The focal length for a positive converging lens in air is the distance from the lens to the point where the incident light beam is focused. It can be](https://pbs.twimg.com/media/E5L_rhPWEAQWxZp.jpg:large)