Question

A tank containing methanol has walls 2.50 cm thick made of glass of refractive index 1.550. Light from the outside air strikes the glass at a 41.3∘ angle with the normal to the glass. Find the angle the light makes with the normal in the methanol. Methanol has a the refractive index of 1.329.

Answer 1

18.6

use snells law for glass n=sini/sinr

the value of angle of refraction in glass becomes value of angle of incidence in the glass methanol interface

use snells law again to get the angle light makes with methanol.