13. Refraction of light

In a transparent medium, light appears to travel in straight lines.

 

  

 

We will discuss about some of our everyday experiences in order to answer these questions.

You may have noticed that the bottom of a water-filled tank or pond appears to be raised. The letters appear raised when a thick glass slab is placed over printed matter and viewed through the glass slab.

 

  

 

It appears to be displaced at the air-water interface.

 

You may have noticed that when viewed from the sides of a glass tumbler containing lemon appears to be larger than it is.

 

  

Consider the case of a pencil that appears to be displaced while partially submerged in water. The light that reaches you from the part of the submerged pencil appears to come from a different direction than the light that reaches you from the part of the pencil above water. The pencil appears to be displaced at the interface as a result of this.

 

The letters appear to be raised for similar reasons when viewed through a glass slab placed over it.

 

If we use liquids like kerosene or turpentine instead of water, does a pencil appear to be displaced to the same extent?

 

 

 

You will notice that the magnitude of the effect varies depending on the media pairs. Light does not travel in the same direction in all media, according to these findings. When light travels obliquely from one medium to another, it appears that the direction of light propagation in the second medium changes. This phenomenon is known as the Refraction of light.