How Do Simple Machines Work Put Pulleys to the Test Sally M Walker and Roseann Feldmann a Lerner Publications Company Minneapolis
For my daughter Chrissie Love you forever RF Copyright 2012 by Sally M Walker and Roseann Feldmann All rights reserved International copyright secured No part of this book may be reproduced stored in a retrieval system or transmitted in any form or by any means electronic mechanical photocopying recording or otherwise without the prior written permission of Lerner Publishing Group Inc except for the inclusion of brief quotations in an acknowledged review Lerner Publications Company A division of Lerner Publishing Group Inc 241 First Avenue North Minneapolis MN 55401 U S A Website address www lernerbooks com Library of Congress Cataloging-in-Publication Data Walker Sally M Put pulleys to the test by Sally M Walker and Roseann Feldmann p cm Searchlight books How do simple machines work Includes index ISBN 978 0 7613 5322 5 lib bdg alk paper 1 Pulleys Juvenile literature 2 Friction Experiments Juvenile literature 3 Gravity Experiments Juvenile literature 4 Force and energy Experiments Juvenile literature I Feldmann Roseann II Title TJ1103 W352 2012 621 8 dc22 Manufactured in the United States of America 1 DP 7 15 11 2010035395
Contents Chapter 1 Chapter 2 WoRk page 4 MACHINES page 8 GRAvIty page 10 FRICtIoN page 19 Chapter 4 Chapter 3 Chapter 5 kINDS oF PuLLEyS page 24 Learn More about Simple Machines 39 Glossary 38 Index 40
