Question

pls i will mark u as brainliest

Anyone explain this..... Plss.... ​

Answer 1

Explanation:

all your question are related with snell's law.

first of all, snell was a scientist who gave a law related with the refraction of light.

law of refraction of light:-

when a light goes from (rarer to denser) or (denser to rarer) it bends towards or away from normal.

and snell told that sine of angle of incidence to the sine of angle of refraction are constant.

$\frac{sini}{sinr } = costant$

on the basis of these information, solution of your question are as follows

1. when a light falls perpendicular on the surface, incident angle becomes equal to 90°and we know that it is equal to zero.hence refracted angle always will be equal to 0°.thats why light doesn't bend.
2. when refractive index of two medium becomes equal, incidence angle becomes equal to refracted angle due to which light goes in a straight line without bending.
3. your 3rd and 4th question are related with bending of light.In first case when light goes from rarer to denser medium,refractive index of rarer medium will be always less than denser medium due to which incidence angle becomes greater than refracted angle.hence light bends towards the normal.
4. in second case when light goes from denser medium to rarer medium, refractive index of denser medium will be greater than rarer medium due to which incidence angle becomes less than refracted angle.that's why light goes away from the normal.