Question

The speed of light in a material is found to be 2.07 x 108 m/s. What is the most likely material from the options below if the speed of light in a vacuum is 3.00 x 108 m/s?

Answer 1

The material is silica quartz.

Step-by-step explanation:

Given that,

Speed of light in material
`v=2.07*10^(8)\ m/s`

Speed of light in vacuum
`c=3.00*10^(8)\ m/s`

We need to calculate the refractive index

Using formula of refractive index

`n=(c)/(v)`

Where, c = Speed of light in vacuum

v=Speed of light in material

Put the value into the formula

`n=(3.00*10^(8))/(2.07*10^(8))`

`n=1.44`

We know that,

Refractive index of silica quartz is between 1.40 to 1.55

So, This is the refractive index of silica quartz.

Hence, The material is silica quartz.

Answer 2

1.3636

Step-by-step explanation:

Write the expression for the refractive index.

n=c/v

c= speed of light in air

v= speed of light in material

=(3×10^8 m/s)/(2.2×10^8 m/s)

=1.3636