Question

A ray of light enters the top of a glass of water at an angle of 36° with the vertical. What is the angle between the refracted ray and the vertical?

Answer 1

`n_a=1.000; \qquad n_w=1.333`
`\theta_i=36^o; \qquad \theta_r=?`

Snell's Law: `n_a\sin\theta_i=n_w\sin\theta_r`
`\theta_r = \sin^{-1}(n_a/n_w\sin\theta_i)=26.16^o`