If the polarizing angle of a piece of glass for green light is `54.74^(@)`, then the angle of minimum deviation for an equilateral prism made of same glass is : `["Given" : tan 54.74^(@)=1.414]`

Options

A. `45^(@)`
B. `54.74^(@)`
C. `60^(@)`
D. `30^(@)`

Answer

D

Explanation

By Brewster's law, `mu=tantheta_(p)`
`or" "mu=tan54.74^(@)`
For an equilateral prism, `angleA=60^(@)`
`therefore" "mu=sin((A+delta_(m))/(2))/sin(A/2)or1.414=sin((60^(@)+delta_(m))/(2))/(sin(60^(@)/2))`
`or" "1/sqrt2=sin((60^(@)+delta_(m))/(2))`
`or" "45^(@)=((60^(@)+delta_(m))/2)rArrdelta=30^(@)`