A spotlight on a boat is y = 2.7 m above the water, and the light strikes the water at a point that is x = 8.6 m horizontally displaced from the spotlight (see the drawing). The depth of the water is 4.0 m. Determine the distance d, which locates the point where the light strikes the bottom.

Answer 1

find the angle between the beam and the normal. Then, the distance from the boat to the point of incidence (use Tan). Then use snell's law to find the angle of refraction. Then, determine the distance from the incident point by TanAngle=distance/depth

add that distance to 8.6 m.

A drawing will help you greatly.