simple machines

Introduces the science behind forces and machines, with examples such as the use of gravity, friction, levers, and pulleys to make machines work. Includes simple experiments.

Presents a short study of how levers, wheels and axles, pulleys, inclined planes, wedges, and screws work, and the importance of these principles in various machines.

Introduces the principles of levers as simple machines, using examples from everyday life.

Defines ramps and wedges and shows how they are incorporated into more complex machines.

Presents a description of springs and describes how they have been incorporated into more complex machines.

Presents a description of screws, in simple text with photographs, and explains how they are used and how they have been incorporated into more complex machines.

Describes wheels and cranks and shows how they have been incorporated into more complex machines.

Explains how levers work, describes different machines that use levers, and tells how to create an example of a lever in a pop-up card.

Discusses the invention of six simple machines in various ancient civilizations from the Stone Age to the fall of the Roman Empire.

Describes various kinds of simple machines, showing how they can be made out of easily obtainable objects and detailing experiments that show how they make tasks easier to perform.