Laws of Refraction of Light

1. What is the Difference between Refraction and Reflection of Light?

Reflection: The bouncing back of light from a smooth and shining surface is called reflection. As per law of reflection, angle of incidence is equal to the angle of reflection i.e. ∠i = ∠r.

Refraction: The bending of light rays, when it travels from one medium to another is called refraction of light. The angle of incidence and the refracted ray may or may not be equal. 

2. What do you mean by Refraction of Light?

The phenomenon of change in the direction/path of light rays when it travels from one transparent medium to another is called refraction of light. 

3. Why does the Sun near the Horizon appear flattened at Sunrise and Sunset?

The horizon appears flattened due to atmospheric refraction. The density and refractive index of the atmosphere decreases with increasing altitude. So, the rays of sun from the top portion and bottom portion are refracted by different degrees.

4. Why do Stars Twinkle?

The stars twinkle due to the atmospheric refraction. The stars’ light under goes undergoes several refractions before reaching the earth, refraction regularly changing the refractive index that’s why it twinkles.

5. Why does a Ray of Light Bend towards Normal as it passes from Air to Glass?

As the speed of light in air is greater than the speed of light in glass. Hence, the ray of light bends towards normal when it passes from air to glass. 

6. How many Laws of Refraction are There?

There are two Laws of Refraction, that are named First Law of Refraction, and Second Law of Refraction.

7. What are the 2 Laws of Refraction?

The 2 laws of the refractions are,

First Law of Refraction of Light: Incident ray, Refracted ray, and Normal to the interface at the point of incidence all lie in the same plane.

Second Law of Refraction of Light: The ratio of the Sine of the Angle of Incidence (i) and the Sine of the Angle of Refraction (r) is constant. It is given as,

sin i / sin r = Constant

Laws of Refraction of Light are the basic laws which govern the refraction of light. As we know light changes its path when it changes its medium and this property is called the refraction of light. The laws of refraction of light are useful in defining the relationship between incident light and refracted light.

When we put a pencil in a glass of water, we observe that the pencil is slightly bent but actually it is not. We also observed that during summer, the trees and houses on the other side of an open ground appear to be shaking. While travelling on a road on a hot summer day, we sometimes observe that water appears in the middle of the road out of nowhere and when we get closer, there is no water. The reason behind all this is the “Refraction of light“. In this article, we will discuss the Refraction of light, the Laws of Refraction and its examples in detail.