The present tutorial will focus on the explanation of the definition of refraction which states a redirection of a wave or the ray of light while passing from one objective medium form another. Based on the concept of physics, the tutorial will include an explanation related to the reason, for which the refraction of light is happen. Moreover, the tutorial will include a discussion regarding the laws of refraction and the effects of refraction along with the applications as well.

What is refraction?

Figure 1: Refraction

  • It is known to all that light travels at the highest speed in the universe. However, while travelling the light goes through several types of surfaces before getting hit by the optics of a human eye that enables them to see properly.

  • In such cases, it has been identified that while travelling through the air while being struck by any kind of surface, the light bends itself (Merriam-webster, 2022). This particular phenomenon of bending the ray of light is recognised as the refraction of light.

Cause of refraction

Figure 2: Cause of refraction

The main cause of being refracted is that the light is always struck by a surface by maintaining a particular angle.

This refractive angle always depends on the reflective index of the media through which the ray of light is travelling. On the other hand, such kind of phenomenon often creates little change in the velocity of the light (Bhaduri et al. 2020).

As a consequence of having a change in the velocity or speed of the light, the light bends slightly after having a contraction with any kind of surface (Sciencedirect, 2022).

For instance, if it is considered that the light that air travels into the water, the speed of light will be decreased as the water is denser in comparison to the air.

Laws of refraction

In order to demonstrate the refraction of light, physics states two types of laws. The first law of the refraction states the refraction ray, incident ray and the normal, all lie on the same point that is placed to the interface of two media. The ratio of the sine angle of incident ray to the sine of the angle of reflection is equal (, 2022). This phenomenon has helped to build up the formula that is depicted as sin i/sin r = constant.

Effect of refraction in nature

In nature, several kinds of effects of the refraction of light can b observed. For instance, the formation of the rainbow after rainfall is considered the natural representation of the refraction of sunlight through the water droplets present in the air (Ramaccia et al. 2020).

  • Before actually crossing the Horison by the sun, the sunlight travels through the atmosphere of earth and stricks against the eye of living beings. Similarly, after sunset, the light of the moon is refracted through the earth's atmosphere before reaching and striking the optics of people's eyes. It is the heterogeneous atmosphere of the earth that causes a blur vision of the twinkling stars in the night sky.

Application of refraction

As lenses are transparent objects, lenses have the ability to refract the rays of light. To use this particular aspect of the lenses, the lenses are generally used in cameras and binoculars (, 2022). In order to have the pictures of far cosmos, in cosmology, this refraction of light is used through the manifestation of lenses in the telescopes.

Refractive index

Figure 3: Reflective index

The refractive index is referred to as the value of the ratio that is calculated by creating a ratio in the speed of light in a vacuum to that in a second medium of density that is grater. The variables of the refractive values are commonly identified by the letter n and n' based on which the descriptive text and various equations are arranged (Britannica, 2022). The formula based on which the refractive index is calculated is displayed as μ = c/v


The main focus of the present tutorial was fixed on the discussion of a concept of physics which is the refraction of light. This tutorial has included an explanation o the definition of the refraction of light along with explaining the application of the refraction such as magnification and seeing Mirage in the desert and many more. Along with that, the tutorial has covered the laws of refraction and the reason for which the refraction of light generally takes place. The laws of the refraction include the statement that at the incident point all rays such as refracted rays, incident rays and the normal all lie on the same plane.


Q1. When does the refraction of waves occur?

The moment of refraction of a light wave is created when a light wave incident at a particular angle from a general source and through passing the boundaries of one medium to another one. In such cases, the velocity of the light wave is generally changed.

Q2. What is the difference between refraction and reflection?

The main difference that lies between reflection and refraction is, in the reflection the light, being originated from one object falls and struck back to the original object, whereas, in the case of refraction, light travels from one spectrum to another by having a slight change in direction of the falling angel.

Q3. What happens at refraction?

As a consequence of the refraction of light, the light that struck to the surface of the lens of a human eye bends. This phenomenon helps people to see and often be confused by making mirages in the places like desert.

Q4. What are the examples of refraction of light?

The process of bending light as it passes from the air into the optics of a person's eye helps to make mirages. The depiction of a bent pencil into water is another example of refraction.



Bhaduri, B., Yessenov, M., & Abouraddy, A. F. (2020). Anomalous refraction of optical spacetime wave packets. Nature Photonics, 14(7), 416-421. Retrieved from:

Ramaccia, D., Toscano, A., & Bilotti, F. (2020). Light propagation through metamaterial temporal slabs: Reflection, refraction, and special cases. Optics Letters, 45(20), 5836-5839. Retrieved from:

Websites, (2022). refractive index. Retrieved from: [Retrieved on 10th June 2022], (2022). Refraction. Retrieved from: [Retrieved on 10th June 2022], 2022. Refraction - an overview. Retrieved from: [Retrieved on 10th June 2022], (2022). Refraction of light. Retrieved from: [Retrieved on 10th June 2022]

Updated on 13-Oct-2022 11:19:47
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