Question

a ray of white light falls from the air onto a glass sheet with an angle of 30 °.

a) What angle will the red and blue white light component rays form between each other inside the glass if the values of the glass refractive indices for these colors are, respectively, n red = 1,612 and n blue = 1,671

b) What will be the values of the frequency and wavelength corresponding to each of these radiations in the glass, if the wavelengths in the vacuum are, respectively, red = 653.3 nm and blue = 486, 1 nm?

Answer 1

a)

For red

By snell's law

Sini/Sinr = n2/n1

Sin30/Sinr = 1.612/1

rred = 18.06o​​​​​​

For blue

By snell's law

Sin30/Sinr = 1.671/1

rblue = 17.398o​​​​​​

So angle between these two rays = 18.06 - 17.398 = 0.66o​​​​​​

b)

Frequency is the property of source so remains same in glass medium also.

For wavelength

Speed = c/refractive index

Speed = fλ = c/n

So λvacuum /λglass = nglass/nair

So for red

653.3/λ glass = 1.612/1

λglass = 405.72 nm

For blue

486.1/λ glass = 1.671/1

λ glass = 290.9 nm