a beam of light passes from water into plyethylene, index of refraction =1.5 if the angle in water is?

Question

57.5 degrees what is the angle in polythylene

Answer 1

Use Snell's law

i=incident, r=refracted
n water= 1.33

ni*sin(Ai)=nr*sin(Ar)

1.33sin(57.5)=1.5sin(Ar)

Ar=arcsin(1.33/1.5*sin(57.5)=48.4 degrees