Refraction and Lenses

The What Is Refraction? Video Tutorial explains what is meant when it is said that light undergoes refraction.

The Optical Density, n, and Light Speed Video Tutorial discusses the relationship and logic that relate the optical density of a material to the speed of light in that material and to the index of refraction of the material.

The Direction of Bending Video Tutorial explains with great detail and numerous examples how to use information about the relative speed, optical density and index of refraction values of two materials in order to predict the direction that light will refract when passes across the boundary between the two materials.

The Snell's Law Video Tutorial discusses the variables that affect the amount of refraction occuring at a boundary and shows how Snell's law of refraction is developed from laboratory data. The video includes two example problems with complete solutions.

The Snells Law and Ray Tracing Video Tutorial discusses the use of Snell's Law and geometric principles in the analysis of complex refraction scenarios. Four example problems are solved.

The Determining the Index of Refraction Video Tutorial utilizes four example problems to demonstrate how to use Snell's Law to determine the index of refraction value of an unknown material. Most of the examples center around lab-like scenarios.

The Total Internal Reflection Video Tutorial discusses the nature of the reflection and refraction of light at the boundary. The discussion leads to an explanation of what total internal reflection is and when it occurs. Numerous graphics and animations assist in the explanations.

The Critical Angle Video Tutorial explains what a critical angle is and why it is important to understanding total internal reflection. The formula for critical angle is derived from Snell's Law. It use in calculating the critical angle for three different boundaries is demonstrated.

The Refraction by Lenses Video Tutorial explains the difference between a converging and diverging lens in terms of their shape and the manner in which they refract light. Numerous examples, illustrations, and animations assist in the explanations.

The Image Formation by Lenses Video Tutorial explains what an image is and how it is formed. The presentation relies upon a collection of animated diagrams showing the behavior of light rays passing through a converging and a diverging lens.

The Drawing Ray Diagrams for Converging Lenses Video Tutorial reviews the three "rules" of refraction for converging lenses and demonstrates how to use the rules to draw a ray diagram for varying locations along the principal axis of a converging lens.

The Object-Image Relations for a Converging Lens Video Tutorial describes how the characteristics of an image formed by a converging lens are dependent upon the location of an object. Numerous examples, illustrations, and animations assist in the explanations.

The Diverging Lens Video Tutorial discusses how diverging lenses refract light and to use such an understanding to construct a ray diagram. The L•O•S•T model is introduced to explain how to describe the image characteristics of diverging lens images. Numerous examples, illustrations, and animations assist in the explanations.

The Mathematics Of Lenses Video Tutorial presents the lens equation and magnification equation and explains how to use them in the solution of algebraic word problems. The video includes four worked-out examples.