Energy and its sources.
Series: Big science
Publisher: Scholastic Inc.
Published: 1992
Place of publication: [New York]
Language: eng
Number of pages: 18
Subjects: Force and energy -- Juvenile literature.; Big books.
Genres: Juvenile literature.
Description: Describes five simple machines--lever, wedge, wheel and axle, screw, pulley, gears, inclined plane--and explains how they work.