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Home Minds On Refraction and Lenses Mission RL3 Optical Density, n, and Refraction Help Help 4

Mission RL3 Optical Density, n, and Refraction

The Question

Consider the following list of materials and their respective index of refraction values. Rank these materials according to the speed at which light moves them from fastest to slowest. List the letters in the appropriate order with no spaces between the six letters; list the fastest first.

Physics Rules

Optical Density and the Speed of Light:
The speed at which light travels through a medium is dependent upon the optical density of that medium. Light travels fastest in media that are least optically dense.

Physics Rules

Optical Density and the Index of Refraction:
Every material is identified by a unique index of refraction value. The index of refraction value is an experimentally determined value that provides a relative measure of the optical density of that material. The higher the index of refraction value, the more optically dense a material is.

Think About It

The optical density of a material is most commonly related to the index of refraction value of that material. The speed of light is often associated in an inverse manner with the optical density of the material through which it is traveling. Here you will have to carefully rank the materials in order of the speed of light by using the relationships stated in the two Know the Law sections.

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