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## How do you calculate the radius of curvature of a lens?

Analytically, the focal length is described by the lens maker’s equation: **1/f = (n – 1)(1/R _{1} + 1/R_{2})**, where R

_{1}and R

_{2}are the radii of curvature, f is the focal length, and n is the index of refraction. Verify that your earlier measurements are consistent with this equation.

## What is the formula of plano convex lens?

**f=R/2**.

## What is radius of curvature of eye?

The cornea has an average radius of curvature of **7.80 mm** with an instrument calibrated for index of refraction of 1.3375.

## What is the focal length of concave mirror?

Focal Length – **The distance between the pole P of the concave mirror and the focus F** is the focal length of the concave mirror. Thus, the focal length of a concave mirror can be estimated by obtaining a ‘Real image’ of a distant object at its focus, as shown in the figure.

## What is the formula of spherical mirror?

Suppose an object is placed u cm in front of a spherical mirror of focal length f such that the image is formed v cm from the mirror, then u, v and f are related by the equation; **1/f= 1/u + 1/v**. This equation is referred to as the mirror formula. The formula holds for both concave and convex mirrors.

## What is the radius of curvature of double convex lens?

The radii of curvature of the surfaces of a double convex lens are **20 cm and 40 cm** respectively, and its focal length is 20 cm.