General

# Reflection and refraction

The Difference between Reflection and Refraction is given here. Reflection is the change in direction that a wave experiences when it comes into contact with the surface that separates two media while returning to the point where it originated. Refraction is the change of direction and speed experienced by a wave incident obliquely on a surface that separates two media with different refractive indices.

## Reflection

It is the change of direction of a wave that, when it comes into contact with the surface that separates two changing media, returns to the point where it originated. The most common examples are the reflection of light, sound, and waves in water.

The reflection of light occurs when light rays hit a surface, collide with it, deflect and return to the medium from which they left at an angle equal to that of the incident light.

In the case of light reflection, we have two laws:

1st. law: The incident ray, the reflected ray, and the normal ray are in the same plane.

2nd. law: The angle of incidence is equal to the angle of reflection.

## Refraction

It is the change of direction and speed that a wave experiences when passing from one medium to another that has a different refractive index. This process only occurs if the wave is incident obliquely on the separation surface of the two media and they have different refractive indices.

Refraction originates from the change in the propagation speed of the wave.

This process can be appreciated when you dip a pencil in a glass of water. The pencil will look broken. It also occurs when light passes through layers of air at different temperatures. Mirages are also an example of refraction.

The deviation in the direction of propagation in refraction is explained by means of Snell’s law. While refraction in non-homogeneous media is a consequence of Fermat’s principle, which establishes that light propagates between two points following the path of the optical path of less time.

suggested video: Reflection vs Refraction

## Difference between Reflection and Refraction

• Reflection occurs when light hits a surface and part of it changes direction and returns in the same direction to the point from which it left. This phenomenon also occurs with sound waves.
• Refraction occurs when invisible light passes through a transparent material, changes direction, and passes obliquely between two media with different indexes of refraction.
• In reflection, light travels in the same medium.
• In refraction, light travels from one medium to another.