Physics

Problem

A light ray in air (

n = 1.00

) strikes a flat glass plate (

n = 1.50

) at an incident angle of

40^{\circ}

. The opposite face of the plate is in contact with liquid ethanol (

n = 1.36

), whose surface is parallel to the first glass face. What is the angle the ray makes with the normal after it has entered the ethanol? a)

40^{\circ}

25^{\circ}

28^{\circ}

23^{\circ}