Question

A beam of light consisting of red, green and blue colours is incident on a right angled prism, fig. The refractive indices of the material of the prism for the above red, green and blue wavelengths are 1.39, 1.44 and 1.47 respectively. The prism will `

A. separate some part of blue colour from red and green colours
B. separate all the three colours from other two colours
C. no separate any colours from other two colours
D. separate some part of red colour from green and blue colours

Answer 1

Correct Answer - 4
`n=(1)/(sin i_(c))=(1)/(sin45^(@)) =1.4142`
As`mu_(g)`and`mu_(b)`are 1.44and1.47 respectively are more than `mu=1.41142`hence the green and blue colours will undergo total internal refelection.for colour `ilti_(c)`hence this colour will get refracted in air.