Sally M Walker

Explains work and machines, discusses how inclined planes work, and describes how they are used.

Using everyday examples, presents an introduction to pulleys along with discussions of simple machines, gravity, and friction. --

Provides experiments to introduce screws as simple machines, including how they function and how they are used in everyday objects to make life easier.

Tells the story of the 1909 coal mine disaster in Cherry, Illinois, that killed hundreds of men, left more than four hundred children fatherless, inspired the first worker's compensation laws, and helped bring about changes in child labor practices.

Defines work, describes machines, and discusses different kinds of pulleys.

Describes the physical characteristics, behavior, life cycle, and endangered status of rays.

What do staircases, dump truck beds, and ramps have in common? All of them are inclined planes! Inclined planes are simple machines. They help us to do jobs more easily. But don't take our word for it. Put inclined planes to the test with the fun experiments you'll find in this book. As part of the Searchlight Books™ collection, this series sheds light on a key science question-How Do Simple Machines Work? Hands-on experiments, interesting photos,...

Audisee® eBooks with Audio combine professional narration and text highlighting to engage reluctant readers! What do jar tops and water-bottle lids have in common? Both of them are screws! Screws are simple machines. They help us to do jobs more easily. But don't take our word for it. Put screws to the test with the fun experiments you'll find in this book. As part of the Searchlight Books™ collection, this series sheds light on a key science question―How...

We've all seen screws, but how do they work? Why is it easier to screw something into something than to simply push it in? With basic hands-on experiments and clear descriptions, this simple machine is explained.