Question

Pls answer this question of the underlined part .[Answer only if you know, no spamming. Spam answer will be deleted and Id will be reported]

Answer 1

Hi friend,

Here is your answer,

When a ray of light incident normally then the angle of incidence is 0°. 
We know the fact that when a ray of light passes from one medium to another of different densities then the ray of light either moves away or towards the normal .
But in this case the ray of light is along the normal so no point of deviation.
Therefore, the ray of light will not deviate from its path.
I have also attached a picture for your help.


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Answer 2

Hi !!!

This is your answer.

Given Question :----

What happens when a light ray is incident normally to the interface of two media?


Answer :----

Let us first talk about incidence of light.
What happens when light is incident on an object?

When light is incident on an object, it either gets refracted or it goes straight.

Here, the light is incident normally.
In other words, the angle of incidence is 0°.

Let us use Snell's law,
According to Snell's law,
Sine (angle of refraction) = Sine (angle of incidence) × refractive index of medium

As angle of incidence is 0°.
We know that sine (0°) = 0.

As sine (angle of incidence) is 0, then the some of angle of refraction will also be 0°.

Hence, from above discussion, we can say that if a ray of light is incident normally to the object, then it will go straight.....


Hope it helps