Ramps and Wedges by Glover, David
	List Price:   $7.49 Unit Price:   $5.99 You Save:   $1.50 (20%) ISBN-10:   1403485941 ISBN-13:   9781403485946 Publisher:   Heinemann Educational Books Category:   Science Books Pub. Date:   May 2006 Pages:   24 Format:   Paperback Ages:   7 to 9
Description/Notes
The most complicated machines often rely on a few simple principles of technology, such as wheels, springs, screws, ramps, and wedges. This series explores these technologies by relating them to common machines in our everyday world from bedsprings to skateboards to zippers. Numerous fact files offer readers fast facts and other pertinent information.