# What is the focal length of plano concave lens?

## What is the focal length of plano concave lens?

The focal length of a plano convex lens is ′f′ and its refractive index is 1.5. It is kept over a plane glass plate with its curved surface touching the glass plate. The gap between the lens and the glass plate is filled by a liquid. As a result, the effective focal length of the combination becomes 2f.

## What is the ratio of the focal length of the two plano convex lens?

2 : 1 : 1.

**What is the focal length of plano convex mirror?**

A plano-convex lens, when silvered on the plane side, behaves like a concave mirror of focal length 60cm. However, when silver on the convex side, it behaves like a concave mirror of focal length 20cm.

**What is the relation between focal length and radius of curvature of a plano convex lens?**

The relation between focal length (f) and radius of curvature (R) of a spherical mirror is that the focal length is equal to half of the radius of curvature i.e. f=R2.

### How is the focal length of a plano convex lens calculated?

The minimum order quantity of plano-convex elements ranges between 100 and 1000 units. The focal length of the lens can be calculated using a simple equation, as follows:

### What is the equation for a convex lens?

In this equation, f is the focal length of the lens, whereas Rf and Rb represent the radii of curvature of the front and back bounding surfaces. For plano-convex lenses, Rf > 0 and Rb = ∞. This article was updated on the 26th October, 2018.

**Why do Plano convex lenses have low spherical aberration?**

Plano-convex lenses have both positive focal lengths and an orientation that plays a crucial role in determining image quality. Low spherical aberration is obtained if the lens is orientated in a way that causes the collimated beam to enter or exit the curved surface, thereby making the plano side face towards the point source or focus.

**What is the task number for a plano concave lens?**

Collection of Solved Problems in Physics Physics Physics Optics Mechanics Thermodynamics Electricity and magnetism Optics A Plano-concave Lens Task number: 1964 A plano-concave lens made of glass of refractive index of \\(1{.}5\\) is located in the air. Its focal length is \\(−10 \\mathrm{cm}\\).