Aray of light in air is incident on a flat piece of glass at an angle of 0 = 54° with respect to the surface. the glass has index of refraction n = 1.8. what is the angle of the refracted ray?

26.71°

Explanation:

Using Snell's law as:

Where,  

 is the angle of incidence  ( 54.0° )

is the angle of refraction  ( ? )

is the refractive index of the refraction medium  (glass, n=1.8)

is the refractive index of the incidence medium (air, n=1)

Hence,  

Angle of refraction = = 26.71°

answer: a. same unit

explanation:

one person pulls 90n one way and the other has 100n pulling the other way.

so the net force = 90 - 100 = -10n,

or the ans can be 10n if the picture shows -90n and 100n instead.