PRACTICE ANOTHER

The figure shows a refracted light beam in linseed oil making an angle of $=31\mathrm{.}0$ with the normal line $N{N}^{\text{'}}.$ The index of refraction of linseed oil is $1\mathrm{.}48.$

$($a$)$ Determine the angle $.$

$($i$)$

Make sure you have correctly identified the angle of incidence and the angle of refraction and are using the correct refractive index of each medium when applying Snell's law to the interface of the linseed oil and air.

$($b$)$ Determine the angle ${}^{\text{'}}.$

You may be neglecting the index of refraction of the linseed oil in calculating the angle of refraction in the water.