Question

She measure the angle of incidence for both the rays on the left side of the box to be 48°6. She knew the refractive index of the material x inside the box was 1.5 what will be the approximate value of angle of refraction?​

Answer 1

Answer:

Let the refractive index of the medium be n and speed of light in air is c.

Using Snell's law of refraction : n air×sini=n

medium×sinr where n air =1

∴ 1×sini=n×sinr ⟹n= sinr×sini

Velocity of light in a medium v= nc= sinic×sinr

⟹v∝sin r

Thus velocity of light is minimum in medium A.

Answer 2

Given:

angle of incidence i = 48.6°

refractive index of the material inside box = 1.5

To find:

angle of refraction r =?

Solution:

Concept- Refractive index of the material given here as 1.5 is the absolute refractive index.

The ratio of the angle of incidence and the angle of refraction always remains constant. This is Snell's law.

This constant is equal to the absolute refractive index.

$n=\frac{sin\:i}{sin\:r}$

$1.5=\frac{sin\:48.6}{sin\:r}$

$sin\:r=\frac{sin\:48.6}{1.5}$

$sin\:r=\frac{0.75}{1.5}$

$sin\:r=0.5$

$r=30^{o}$

Answer:

The approximate value of angle of refraction will be 30°.