Question

Observe the following table :
Material medium
Refractive index
P= 1.52
Q= 1.44
R=2.42
S=1.33
In which material medium speed of light is very high?
B. S
A. Q
D. P
C. R​

Answer 1

Answer:

The speed of light is maximum in S = 1.33 material.

Explanation:

What is refractive index:

• The ratio of the speed of light in a vacuum to the speed of light in a second medium of larger density is used to determine the Refractive Index (Index of Refraction).

• Refraction is caused by a change in light speed, and refraction is highest where the light speed changes the most.

Speed of light through materials:

• The speed of a substance is related to its optical density, which is related to its index of refraction.
• The least dense material is air, which has the lowest index of refraction value, while the densest material is water (largest index of refraction value).
• As a result, it's logical to assume that the most refraction happens when light is transmitted through an air-water barrier.

Result:

• As the speed of light through a denser medium increases, the refractive index will increase.

• Here, the refractive index will be more for a more denser medium as the speed of light through a denser medium will be lesser.

• Hence, the speed of light is maximum in the S which has the lowest refractive index.

Answer 2

Explanation:

Given - The refractive indices of P, Q, R and S

(P= 1.52

Q= 1.44

R=2.42

S=1.33)

Formula for refractive index,

$n=\frac{c}{v}$

n is refraction index

c is speed of light in vaccume

v is speed of light in medium

The refractive index of a medium (n) is equal to the speed of light (c) divided by the velocity of light through the medium (v). Thus, the refractive index of a medium is inversely proportional to the speed of light in the medium, i.e., with an increase in refractive index, a decrease in the speed of light is observed, and vice versa.

Therefore, medium S, having the lowest refractive index, will have the highest speed.