Question

Question #354d2

Answer 1

41.81 degrees

Explanation:

Critical angle of light is that one,if at that angle light falls at an interface,while going from a solid to lighter media,it will not enter the media next to the interface,rather go along the interface,

So,using Snell's law we can say,
`u1 sin theta` = `u2 sin alpha`
Given, `u2` = `(3/2)`
And `sin theta` = 1
So, `sin alpha` =`2/3` or `alpha` = 41.81 degrees

Answer 2

the critical angle is `i_c=42.067`

Explanation:

critical angle `i_c` is given as
`sin(i_c)=1/n_21` where `n_21=n_2/n_1`
`n` is the refractive index of that particular media
`here n_2=3/2 and n_1=1` substituting in the formula we get
`sin(i_c)=(1/(3/2))=(2/3)rArri_c=sin^-1(2/3)=sin^-1(0.67)`
`rArri_c=42.067`