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## What is the formula of radius of curvature of convex 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.

## How do you find the radius of curvature of a convex mirror?

**If you find the focal length of the convex mirror formed by the cornea**, then you know its radius of curvature (it’s twice the focal length).

## How do you find the focal length of a convex lens if the radius of curvature is given?

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.

## What is the radius of convex lens?

It has been given that the radius of curvature for a convex lens is **40 cm**, for each surface.

## Is radius of curvature and centre of curvature same?

No, a centre of curvature and the **radius of curvature is not the same**.

## Is the radius of curvature of a convex mirror negative?

The radius of curvature r is **positive** for a convex refracting surface and negative for a concave refracting surface.

## What is the radius of curvature of the mirror its focal length is 20cm?

The radius of curvature is double the numerical value of the focal length of a spherical mirror. (The focal length is a point on the principal axis where rays coming parallel to the axis from infinity meet.) Therefore, the answer is option (D); **40 cm**.

## How do you solve a convex mirror equation?

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 a convex mirror which forms an image one fourth?

**R = 2f = 240 cm**.