Chapter 17 - Light and Image Formation

Announcements Reflection and Refraction Image Formation Final QuestionsRefractionWhen light passes from one medium to another, its speed instantly changesAs light travels from one medium to another, its frequency does not change but its wavelength doesIndex of refractionThe index of refraction is a dimensionless numberThe index of refraction of a medium is inversely proportional to the wave speed in that mediumThe higher the index of refraction of a medium, the more it slows light down and the more itbends lightObservationsIf n 2 is equal to n 1 , then θ 2 is equal to θ 1 . In this case, refraction does not bend the light beam, whichcontinues in an undeflected directionIf n 2 is greater than n 1 , then θ 2 is less than θ 1 . In this case, refraction bends the light beam away fromthe undeflected direction and toward the normalIf n 2 is less than n 1 , then θ 2 is greater than θ 1 . In this case, refraction bends the light beam away fromthe undeflected direction and away from the normalLight and Image Formation