How did workers in ancient civilizations move the huge stones they used to build cities?
They rolled the stones over logs much like a modern-day conveyor belt.
Inside, You'll Find:
How humans have used simple machines throughout history;
A timeline, photos-and how simple machines can be combined to do different jobs;
Surprising True facts that will shock and amaze you!
Table of Contents
1 Easy Does It
How do simple machines make work easier? 7
2 Getting Around
How do wheels and pulleys work? 15
3 Lift and Lower
How do levers move loads? 23
So Many Simple Machines!
Can you find simple machines at an amusement park? 28
4 Ramp it Up
How do inclined planes help raise objects higher? 31
5 Break Apart and Hold Together
How do wedges and screws convert forces? 35
True Statistics 43
Important Words 46
About the Author 48