Refraction of Light

Refraction of Light - Definition, Examples, FAQs

Edited By Team Careers360 | Updated on Jun 01, 2022 01:36 PM IST

Refraction Definition

Refraction meaning is the direction of light changes when it goes from one medium to another at the interface. Refraction of light is the phenomenon of a change in direction at the interface of two media.
$File:Light-refraction-glass-prism.svg$

Light refraction is one of the most well-known phenomena, but other waves, such as sound and water waves, can also refract. We may use optical equipment like magnifying glasses, lenses, and prisms because of refraction. We may also focus light on our retina because of refraction of light.

Also read -

Latest: JEE Main: high scoring chapters | Past 10 year's papers

Don't Miss: Most scoring concepts for NEET | NEET papers with solutions

New: Aakash iACST Scholarship Test. Up to 90% Scholarship. Register Now

This Story also Contains

Refraction Definition
Refraction of light
State the laws of refraction of light
What is refraction
What is refraction of light?
What Causes Refraction?
Refraction of Light Examples

State the laws of refraction of light

$File:Refraction9.png$

1. At the point of incidence, the incident ray, refracted ray, and normal to the interface of two transparent media all lie in the same plane.

2. For a given hue of light and a given set of media, the ratio of sine of angle of incidence to sine of angle of refraction is constant. Snell's law of refraction is another name for this law.

sin i/ sin r = N

The refractive index of the second medium in relation to the first is also known as this constant.

What is refraction

Refraction is a term that is used to describe how light bends

The direction of a light ray changes when it strikes the surface separating two media. The refraction of light is the name for this phenomenon. In a vacuum, the speed of light is greatest. Light moves at a slower rate in any medium. The direction of light changes as a result of this at the interface of two distinct media.

The incident light's frequency remains constant, but its speed and wavelength fluctuate. When a light beam enters a denser medium, it bends closer to the normal, whereas it shifts away from the normal in a lighter medium.

Related Topics Link,

What is refraction of light?

The ray of light bends towards normal when moving from a rarer to a denser medium, and away from normal when moving from a denser to a rarer medium.

What Causes Refraction?

When a light beam is incident on the interface of two mediums, its frequency (v) remains constant. Light, on the other hand, travels at various speeds in different materials.

c = vλ

As a result, the wavelength (μ) of light at the interface varies. This, in turn, generates refraction, or a shift in direction. During refraction, it is clear that

The frequency of light does not change.

The incident light deviates due to changes in light speed and wavelength.

Refractive index

$File:Refractive index pic.png$

According to Snell's law of refraction, if the angle of incidence is I and the angle of refraction is r on the interface of two mediums,

sinθᵢ/sinθᵣ= μ equals constant

With regard to the first media, this constant is known as the relative Refractive Index of the second medium (refracted ray propagates here) (incident ray propagates here). The absolute refractive index is calculated using vacuum as the first medium.

The absolute refractive index of a media is given by, if the speed of light in that medium is

μ = cv

In a vacuum, c is the speed of light. is always more than 1 (for example, the refractive index of glass is 1.51), and is equal to 1 only in vacuum. For a dense medium, it is higher. Snell's law can be expressed in terms of the absolute refractive indices 1 and 2 of the two media as follows:

μ₁sini = μ₂sinr

The incident angle I and the refracted angle r are the incident and refracted angles, respectively.

Light physics

What is the role of light in physics? Light is electromagnetic radiation that the human eye can detect. Electromagnetic radiation has a wide range of wavelengths, ranging from gamma rays with wavelengths less than 1 × 10−11 metres to radio waves with wavelengths measured in metres.

Refraction of light for class 10

The change in direction of a wave travelling from one medium to another caused by its change in speed is known as refraction in physics. In deep water, for example, waves travel faster than in shallow water. Sound waves travel faster inside of the warm air than in cold air.

Also Read:

Refraction of Light Examples

In a clear medium, light seems to travel in straight lines.

When light passes through one clear substance and into another, what happens? Is it still moving in a straight line or has it changed its course? We'll talk about some of our everyday experiences.

Consider the situation of a pencil that appears to be displaced while partially submerged in water. In comparison to the part above water, the light reaching you from the portion of the pencil inside water appears to emanate from a different direction. The pencil appears to be shifted at the interface as a result of this. When viewed through a glass slab put over it, the letters appear to be lifted for similar reasons.

If a pencil is used instead of a pen, does it appear to be displaced to the same extent?

$File:Refraction of a pencil.svg$

Rarer and denser medium

The denser medium is the one with a higher refractive index, whereas the rarer medium is the one with a lower refractive index. The refracted ray bends towards the normal when the wave moves from a rarer to a denser medium, and the angle of refraction is less than the angle of incidence.

Also check-

JEE Main Highest Scoring Chapters & Topics

Just Study 40% Syllabus and Score upto 100%

Download E-book

NCERT Physics Notes:

Frequently Asked Question (FAQs)

1. Why is it so difficult to photograph a fish swimming in water?

It's tough to photograph a fish swimming in water due to light refraction.

The reason for this is that the light beams that travel from the fish to the shooter curve at the water-air boundary. As a result, the shooter only sees a picture of the fish, not the actual creature

2. Describe how a mirage form

On a hot summer day, the air directly above the road surface is extremely hot, whereas the air at higher elevations is cool.

The refractive index of air increases with density, as we all know.

As a result, the colder air towards the top has a higher refractive index than the hotter air near the road.

The hotter, thinner air goes faster than the cooler, denser air above it.

The temperature drops with height on hot days.

As a result, the refractive index of air rises with altitude.

3. What is the status of the optical fibres? What are the several applications of optical fibres in our daily lives?

An optical fibre is a very thin glass or plastic fibre with a radius of around a micrometre (10-6 m).

A light pipe is formed by a group of such tiny fibres.

4. When does a light ray at the interface of two media not deviate?

When a light ray is incident perpendicular to a surface's interface, it does not deviate.

When a light beam strikes a surface at a greater than critical angle, it does not refract but instead reflects back into the original medium.

5. When we sit around a campfire, what are the reasons for the items swaying beyond the fire?

The temperature of the surrounding air changes as a result of the campfire's heat convection.

This causes a constant change in the density and refractive index of air.

The refractive index of air changes with time, changing the refracted path of light ray