Question

After a beam of UV light with the wavelength of 300 nm in the vacuum travels from vacuum into a glass, its wavelength changes to 250 nm. What is the refractive index of this glass for this light beam? Please keep 2 significant figures.

Answer 1

1.2

Step-by-step explanation:

First find the frequency of UV light as follows:

`f=(c)/(\lambda)\\f=(3*10^8)/(300*10^(-9))=10^(15)Hz`

The frequency does not change when light enters from vacuum into glass.

`v=f\lambda\\v=10^(15)* 250*10^(-9)=2.50*10^8m/s`

Refractive index of glass can be calculated as follows:

`\mu=(c)/(v)`

where, v is the velocity of UV light in glass.

`\mu=(3*10^8)/(2.5*10^8)=1.2`