Understand the basics of geologic stresses in this study guide.

Wikipedia provides an encyclopedia entry about concrete that features pictures, diagrams, history and other information, as well as links to related topics.

Especial Gas Inc. provides a good description of what CFCs are and the dates that countries started to ban them. Explains where the name freon came from.

From the Cambridge Engineering Selector web site. Contains a lengthy list of definitions of a variety of material properties related to solid strength and elasticity (and more). Definitions are accompanied by equations and metric unit...

This lesson will explain how to calculate net forces on an object being pushed or pulled. It is 4 of 4 in the series titled "Calculating Forces."

This lesson will explain how to calculate net forces on an object being pushed or pulled. It is 1 of 4 in the series titled "Calculating Forces."

This lesson introduces the concept of tension. It is 1 of 2 in the series titled "Introduction to Tension."

The expansion-compression-condensation cycle of a refrigerator is discussed and explained. Understandable language but no graphics.

The expansion-compression-condensation cycle of a refrigerator is discussed and explained. Understandable language but no graphics.

A question and answer format is used to relate elastic potential energy to the bounce of a rubber ball. Explanation of this simple phenomenon is thorough, complete, and free of trite statements.

The operation of conventional air conditioners are described. Their parts and the refrigerant/heat exchange cycle is discussed. The use of alternative geothermal systems are explained.

Great animations showing how sound is produced.

This introductory tutorial introduces students to basic symbols and notation in music.

Disney