Difference Between Reflection and Refraction

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Reflection and Refraction

The phenomenon that is of reflection is said to be the change in direction of a wavefront that is at an interface which is in between two different media. The very common examples that include the lights reflection water and sound waves. 

In physics, we have seen that refraction is the change in direction of a wave that is passing from one medium to another medium or from a gradual change in the medium. How much a wave is refracted is said to be determined by the change in the speed of the wave and the initial direction which is of wave propagation relative to the change in the direction and in speed.

Difference Between Reflection and Refraction of Light

The direction in rays of light change when they reflect from a surface and when they travel from one transparent medium into another or travel through a medium whose composition is continuously changing. 

When light passes through different mediums, of two different phenomena happen. They are refraction and reflection. Let us now discuss what is the difference between refraction and reflection.

  • Reflection: When a light ray that comes back into the same medium after striking the surface of another medium, then the phenomenon is known as the reflection of light. In other words, we can easily say that the reflection is the bouncing back of the light rays from a surface that is in the same medium.

  1. Regular Reflection: The reflection which is regular is also termed as specular reflection occurs when the light beam falls on a regular and polished plane which is smooth.

  2. Irregular Reflection: The reflection which is Irregular also termed as diffuse reflection occurs when the beam of light falls on the rough surface and then the light reflects in various directions.

  • Refraction: The change of speed of light and the direction as it enters from one medium to another is termed as the refraction of light. Examples of this phenomenon we can take as refraction are lenses, prism, and telescopes.

In this phenomenon, the wave is diverted when it passes diagonally through the interface which is between two media of different densities. It refers clearly to the shift in speed and the direction and speed of the beam of the wave of light this is because of the change in the medium of transmission.

Reflection and Refraction are the two major phenomena which are related to the propagation of beams of light. The crucial difference between refraction and reflection is that reflection is the act of the rebounding of the wave of light in the same medium after striking the boundary of a medium which is different. On the other hand, the process of refraction is the phenomenon of bending rays of light towards a different medium after interacting with the boundary of that medium.

Refractive Index

The process of refractive index is the ratio of the angle of incidence to the angle of refraction. It determines very clearly that the speed of a ray of light in the new medium. This implies to us that the denser the medium, light travels at a slower speed and vice versa.

Angles of Incidence, Reflection, Refraction

In the process reflection, the ray which strikes the smooth surface is known as the incident ray. The ray which reflects back that too from a smooth surface is known as a reflected ray. The angle in between the incident ray and the normal ray is known as an angle of incidence and the angle which is between the normal ray and reflected ray is known as the angle of reflection.

Refraction is the process in which when the incidence ray strikes the surface in some medium and it gets diverted or bent while passing through the medium.

The ray generally bends towards normal ray while travelling to rarer medium from a medium which is denser and it bends away from normal ray while travelling to a denser medium from a medium which is rarer.

Light Waves

The processes of reflection and refraction are the two most basic characteristics of a wave of light waves. We already know that the radiations which are said to be the electromagnetic radiation ranging from 400 to 750 nm are known as light. The eye of a human is sensitive to this specific range of wavelength and thus is able to detect it. Light and our own sense of vision that are the two main factors which allow the interpretation of objects that are around us. 

FAQ (Frequently Asked Questions)

1. What are examples of reflection and refraction?

An example of reflection is if we are facing north, then our reflection is facing south. The light reflection of the rays is one of the major aspects of geometric optics. Example of refraction is bending of objects when underwater.

2. What are the two types of refractive indices?

The relative refractive index is said to be the ratio of the speed of light in one medium to the speed in another medium. The absolute refractive index is said to be the ratio of light in a vacuum to the speed of light in another medium.

3. Explain refraction.

The process of refraction is the bending of light as when it passes from one substance to another. For example, rays of light passing from air to glass and back to air again. This whole process of bending is caused by the differences in density between the two substances.