Question

The speed of the light in diamond is 1, 24, 000 km/s. Find the refractive index of
diamond if the speed of light in air is 3, 00,000 km/s.

Answer 1

$\bigstar$ Given

The speed of the light in a diamond is 1,24,000 km/s

The speed of light in air is 3,00,000 km/s

$\bigstar$ To Find

The refractive index of diamond

$\bigstar$ Solution

We know that

$\red{\sf \longrightarrow n=\dfrac{c}{v}}$

Here

• n = refractive index of medium
• c = speed of light in air
• v = velocity of light in medium

According to the question

Hence

The medium is diamond

And

We are asked to find the the refractive index of diamond

Therefore

We must find "n"

Given that

The speed of the light in a diamond is 1,24,000 km/s

The speed of light in air is 3,00,000 km/s

Hence

• v = 1,24,000 km/s
• c = 3,00,000 km/s

Substituting the values

We get

$\green{\sf \longrightarrow n=\dfrac{3,00,000}{1,24,000}}$

On further simplification

We get

$\orange{\sf \longrightarrow n=\dfrac{300}{124}}$

Hence

$\pink{\sf \longrightarrow n=2.4}$

Therefore

The refractive index of diamond = 2.4

Answer 2

Answer:

=2.4

Explanation:Given: The speed of the light in a diamond is 1,24,000 km/s, the speed of light in air is 3,00,000 km/s

To find the refractive index of the diamond

Solution:

We know,  

Refractive index of the medium=  

Speed of the medium in air

Speed of light in air

​  

 

⟹Refractive index of diamond=  

124000km/s

300000km/s

​  

=  

124

300

​