The value of τ α can be calculated by knowing the angle of refraction ( θ 2) and the extinction coefficient of the material ( k), as well as the thickness of the material or distance that light must propagate through ( d). Test your understanding of the concepts covered with the reflection and refraction problem set. Below is a video overview of the concepts covered. The interactive illustration at the top of this page explores patterns of reflection and refraction of light rays that hit a variety of interfaces at different angles of incidence. A light ray with an angle of incidence equal to or greater than the critical angle will reflect, following the law of reflection. For light traveling from a more dense to a less dense medium, there is a critical angle * beyond which the light will not pass through the interface.The greater the incident angle, the greater the refraction.The greater the difference in density * between the two media, the greater the refraction.This behavior is exhibited by light moving from air into water. Light traveling from a less dense to a more dense medium refract towards the normal.This behavior is exhibited by light moving from water to air. Light traveling from a more dense to a less dense medium refract away from the normal.Refracted light rays behave in the following ways: The direction and magnitude of refraction depends on the relative densities of the two media and the angle of incidence. Light rays that pass through an interface are transmitted rays. The law of reflection states that the angle of reflection * is equal to the angle of incidence. Light rays that reflect follow the law of reflection. The path a light ray will follow after hitting a surface can be predicted based on the incident angle and information about the surface. This angle is defined as the angle the incident ray makes with a line normal * (perpendicular) to the surface. The angle it hits the surface is the angle of incidence. The following terms are used to describe the behavior of light rays: The light ray that hits a surface is the incident ray *. The behavior that dominates depends on the type of interface and the angle at which the light ray falls on the surface. Passes from one medium into the other and continue on a new, straight line path.Reflects off the surface and travels off in a different direction.When a light ray encounters a surface, one or more of the following three things occur, the light ray: This makes it possible to predict the path a light ray will follow as it move from its point of origin to wherever it eventually changes into another form of energy such as heat.Įveryday examples of light encountering surfaces include movement of light from air into the water in a swimming pool, through the glass of a window pane or onto an opaque surface such as a rock or the back of your hand. The model also assumes that light rays behave in a predictable manner when they encounter surfaces such as an interface between different media (air and water for example) or the surface of an opaque object. The light ray model makes the assumption that light travels in a straight line through transparent media such as air or water. Many sources (including other pages on this site) refer to this angle as the angle of refraction *. *note - In this illustration the angle of the transmitted ray is called the angle of transmission and labeled as θ t.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |