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Table of Contents
 
Other Titles by Janice VanCleave
Title Page
Copyright Page
Dedication
Introduction
How to Use This Book
General Instructions for the Exercises
General Instructions for the Activities
 
Chapter 1 - Push and Pull
 
What You Need to Know
Activity: SHAPELY
 
Chapter 2 - Blast Off
 
What You Need to Know
Activity: UNBALANCED
 
Chapter 3 - Up and Away
 
What You Need to Know
Activity: LIFTER
 
Chapter 4 - Up and Down
 
What You Need to Know
Activity: AROUND AND AROUND
 
Chapter 5 - Coming Through
 
What You Need to Know
Activity: PASSING THROUGH
 
Chapter 6 - Easy Listening
 
What You Need to Know
Activity: QUIET PLEASE
 
Chapter 7 - Stop and Go
 
What You Need to Know
Activity: PASSING THROUGH
 
Chapter 8 - Directors
 
What You Need to Know
Activity: UP OR DOWN
 
Chapter 9 - Recover
 
What You Need to Know
Activity: SEPARATE
 
Chapter 10 - Break Out
 
What You Need to Know
Activity: STICKERS
 
Chapter 11 - New Stuff
 
What You Need to Know
Activity: GOO
 
Chapter 12 - Hot Stuff
 
What You Need to Know
Activity: MORE
 
Chapter 13 - Brighter
 
What You Need to Know
Activity: EXTRA YELLOW
 
Chapter 14 - Primary
 
What You Need to Know
Activity: BREAK UP
 
Chapter 15 - Shiny
 
What You Need to Know
Activity: PUNCH DESIGNS
 
Chapter 16 - The Limit
 
What You Need to Know
Activity: HOW MUCH?
 
Chapter 17 - Weakened
 
What You Need to Know
Activity: TIRED
 
Chapter 18 - Discarded
 
What You Need to Know
Activity: TILTED
 
Chapter 19 - Less Is More
 
What You Need to Know
Activity: FILL ’ER UP
 
Chapter 20 - Flowing Through
 
What You Need to Know
Activity: MORE
 
Chapter 21 - Shake Up
 
What You Need to Know
Activity: SIDE-TO-SIDE
 
Chapter 22 - Changes
 
What You Need to Know
Activity: SPINNER
 
Chapter 23 - Around and Around
 
What You Need to Know
Activity: COVERED
 
Chapter 24 - Neighbors
 
What You Need to Know
Activity: BAG IT
 
Chapter 25 - Stringy
 
What You Need to Know
Activity: STRONGER
 
Glossary
Index

Other Titles by Janice VanCleave
Science for Every Kid series:
Janice VanCleave’s Astronomy for Every Kid
Janice VanCleave’s Biology for Every Kid
Janice VanCleave’s Chemistry for Every Kid
Janice VanCleave’s Constellations for Every Kid
Janice VanCleave’s Dinosaurs for Every Kid
Janice VanCleave’s Earth Science for Every Kid
Janice VanCleave’s Ecology for Every Kid
Janice VanCleave’s Energy for Every Kid
Janice VanCleave’s Food and Nutrition for Every Kid
Janice VanCleave’s Geography for Every Kid
Janice VanCleave’s Geometry for Every Kid
Janice VanCleave’s The Human Body for Every Kid
Janice VanCleave’s Math for Every Kid
Janice VanCleave’s Oceans for Every Kid
Janice VanCleave’s Physics for Every Kid
Spectacular Science Projects series:
Janice VanCleave’s Animals
Janice VanCleave’s Earthquakes
Janice VanCleave’s Electricity
Janice VanCleave’s Gravity
Janice VanCleave’s Insects and Spiders
Janice VanCleave’s Machines
Janice VanCleave’s Magnets
Janice VanCleave’s Microscopes and Magnifying Lenses
Janice VanCleave’s Molecules
Janice VanCleave’s Plants
Janice VanCleave’s Rocks and Minerals
Janice VanCleave’s Solar System
Janice VanCleave’s Volcanoes
Janice VanCleave’s Weather
Also:
Janice VanCleave’s 200 Gooey, Slippery, Slimy, Weird, and Fun Experiments
Janice VanCleave’s 201 Awesome, Magical, Bizarre, and Incredible Experiments
Janice VanCleave’s 202 Oozing, Bubbling, Dripping, and Bouncing Experiments
Janice VanCleave’s 203 Icy, Freezing, Frosty, and Cool Experiments
Janice VanCleave’s 204 Sticky, Gloppy, Wacky, and Wonderful Experiments
Janice VanCleave’s Great Science Project Ideas from Real Kids
Janice VanCleave’s Guide to the Best Science Fair Projects
Janice VanCleave’s Guide to More of the Best Science Fair Projects
Janice VanCleave’s Science Around the Year
Janice VanCleave’s Science Through the Ages
Janice VanCleave’s Scientists
Janice VanCleave’s Science Around the World

001

This book is dedicated to a very loving lady
and a special person in my life:
my daughter Ginger Russell.

Introduction
This is a basic book about engineering that is designed to teach facts, concepts, and problem-solving strategies. Each section introduces concepts about engineering that make learning useful and fun.
 
Engineering is the application of science, mathematics, and experience to produce a thing or a process that is useful. Engineering is neither more nor less important than science, just different. The basic objective of science is to discover the composition and behavior of the physical world; that is, science is a study of the natural world. The basic objective of engineering is to use scientific principles and methods to produce useful devices and services that serve humankind.
 
Examples of the work of engineers include making things like buildings, bridges, and airplanes and designing useful services, such as ways to clean up an oil spill in the ocean or to keep flood waters out of low-lying areas. Since useful things and processes must “obey” the laws of nature, engineers must understand and use these laws. Although engineering and science are two separate fields of study, in practice the work of real-world scientists and real-world engineers overlaps to some degree. For example, scientists use engineering ideas when they design instruments for experiments, and engineers use scientific experiments when they test the laws of nature in order to develop new things.
 
This book will not provide all the answers about engineering, but it will offer keys to understanding more about the work of engineers. It will guide you to answering questions such as, What wing shape gives airplanes their lift? How does knowledge about density help determine the best materials for fire control? What types of instruments do meteorological engineers design and test?
 
This book is designed to teach engineering concepts so that they can be applied to many situations. The problems, experiments, and other activities are easy to understand. One of the main objectives of the book is to make learning about engineering fun.

How to Use This Book

Read each chapter slowly and follow procedures carefully. New terms are boldfaced and defined in the text when first introduced. So if you do not read the chapters in order, you may need to look in the Glossary for unfamiliar science terms. The format for each section is:
What You Need to Know: Background information and an explanation of terms.
Exercises: Questions to be answered or situations to be solved using the information from What You Need to Know.
Activity: A project to allow you to apply the skill to a problem-solving situation in the real world.
Solutions to Exercises: Step-by-step instructions for solving the Exercises.
All boldfaced terms are defined in the Glossary at the end of the book. Be sure to flip back to the Glossary as often as you need to, making each term part of your personal vocabulary.

General Instructions for the Exercises

1. Study each problem and solution carefully by reading it through once or twice before answering.
2. Check your answers in the Solutions to Exercises to evaluate your work.
3. Do the work again if any of your answers are incorrect.

General Instructions for the Activities

1. Read each activity completely before starting.
2. Collect needed supplies. You will have less frustration and more fun if all the necessary materials for the activities are ready before you start. You lose your train of thought when you have to stop and search for supplies.
3. Do not rush through the activity. Follow each step very carefully; never skip steps, and do not add your own. Safety is of utmost importance, and by reading each activity before starting, then following the instructions exactly, you can feel confident that no unexpected results will occur.
4. Observe. If your results are not the same as described in the activity, carefully reread the instructions and start over from step 1.

1
Push and Pull
Structural Engineering

What You Need to Know

Structural engineering is the branch of engineering concerned with the design and construction of all types of structures such as bridges, buildings, dams, tunnels, power plants, offshore drilling platforms, and space satellites. Structural engineers research the forces that will affect the structure, then develop a design that allows it to withstand these forces.
 
A force is a push or a pull on an object. The two basic forces on a structure are lateral forces (forces directed at the side of a structure) and vertical forces (forces directed up or down on a structure). Lateral forces on a structure might include wind (moving air).
 
The main vertical force on a structure is gravity (force pulling an object downward, which is toward the center of Earth). Weight is the measure of the force of gravity on an object. The weight of an object depends on mass, which is the amount of substance in the object. The greater the mass, the greater the weight; thus, the greater the force of gravity.
 
Engineers refer to the gravity force acting on a structure as the sum of its dead and live forces. Dead forces are the weight of the permanent parts making up the structure. In a building, dead forces include the weight of the walls, floors, and roof. Live forces are the weight of temporary objects in or on a structure. In a building, live forces include the weight of people, furniture, and snow on the roof. In the figure, live forces include the weight of the wagon, the child, and the boy; dead forces include all the parts making up the bridge. The total gravity force acting on the bridge is shown by the arrow directed downward.
 
Since shapes of materials affect their strength, structural engineers must consider what shapes to use in designing structures that will stand up to both lateral and vertical forces.
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Exercises
1. In a building, which choice represents a live force?
a. floors
b. windows
c. desk
2. Which force in the figure, A, B, or C, is the lateral force?
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Activity: SHAPELY

Purpose To determine how the shape of a material can make it stronger.
 
Materials
2 books of equal thickness ruler
1 sheet of copy paper
15 or more pencils
Procedure
1. Lay the books on a table so that they are 6 inches (15 cm) apart.
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2. Use the sheet of paper to make a bridge between the two books. Make sure that an equal amount of the paper lies on each book.
3. Test the strength of the paper bridge by gently placing one pencil at a time in the center of the paper (between the books) until the paper falls.
4. Remove the paper from the books and fold it in half by placing the short ends together. Fold the paper again in the same direction.
5. Unfold the paper, then bend it accordion style to form an M shape.
6. Use the folded paper to form a bridge between the books as shown. Again, make sure that an equal amount of the paper is on each book.
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7. Test the strength of the paper bridge by gently placing one pencil at a time across the top of the folded paper. If the pencil(s) tends to roll, use your finger to stop it. Count the pencils that the paper will support before falling.
8. Remove the M-shaped bridge and press its sides together. Then fold the paper in half, placing the long sides together.
9. Unfold the paper and bend it accordion style as before. The paper now has a double-M shape.
10. Place the paper bridge across the books.
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11. Repeat step 7 with the double-M bridge.
Results The unfolded paper will not support even one pencil. Depending on the weight of the pencils, the M-shaped bridge may hold 4 to 6 pencils. The double-M bridge will hold more than twice as many pencils as the single-M bridge.
 
Why? A flat piece of paper is not very strong, but when it is folded in an accordion shape, it becomes stronger and can support more weight. This is because all of the object’s weight pushes down on one part of the flat paper. But on the folded paper, the object’s weight is spread out and smaller forces push down on different parts of the paper. The more folds, the more spread out the weight. For example, corrugated cardboard, which has a layer of grooves and ridges, is much stronger than flat cardboard.
Solutions to Exercises
1. Think!
• Floors are part of a structure, so they are permanent forces (dead forces).
• Windows are part of a structure, so they are permanent forces (dead forces).
• A desk is not part of a structure, since it can be removed easily, so it is a temporary force—that is, a live force.
Choice C is a live force.
 
2. Think!
• A lateral force pushes or pulls on the side of a structure.
• Force A shows snow on the roof. Snow adds weight to the house, so it is a gravitational force.
• Force B shows a window in the house. Windows add weight to the house, so force B is a gravitational force.
• Force C shows wind hitting against the side of the house.
Force C represents a lateral force.

2
Blast Off
Aerospace Engineering

What You Need to Know

Aerospace engineering is the branch of engineering concerned with the design, manufacture, and operation of launch vehicles, satellites, spacecraft, and ground-support facilities for the exploration of outer space. One type of spacecraft is a rocket, which is powered by gases that are forced out of one end. Rocket-like devices were demonstrated about 360 B.C. by the Greek mathematician and scientist Archytas (428-350 B.C.). So while some form of a rocket has been in existence for many years, the science of how a rocket works was first described by the British scientist Sir Isaac Newton (1642-1727) in 1687. Newton stated three important scientific principles that govern the motion of all objects, whether on Earth or in space. These principles, now called Newton’s laws of motion, provided engineers with the basic knowledge necessary to design modern rockets such as the Saturn V rockets and the Space Shuttle Discovery.
 
Newton’s first law of motion is a law about inertia, which is the tendency of an object at rest to remain at rest and an object in motion to remain in motion. An unbalanced force is needed to change the motion of an object; that is, the force starts or stops the motion of an object. When two or more forces act on an object, if the forces are equal and in opposite directions, the difference between the value of the forces is zero; thus, they are balanced and there is no motion. But if the forces are not equal in value, the difference between their value produces an unbalanced force (sum of unequal forces acting on an object). For example, if two boys are pulling on the ends of a rope in opposite directions and if one boy pulls with more force to the left, the resulting unbalanced force makes the rope and the boy holding the right end move to the left.
 
Newton’s second law of motion explains how the force needed to accelerate (speed up) an object depends on the mass of the object. It takes more force to accelerate a car the same distance as a baseball because the car has a greater mass than the baseball. The same is true of deceleration, which means to slow down.
 
Newton’s third law of motion explains that forces act in pairs. This law states that for every action there is an equal and opposite reaction. Newton realized that if one object applies a force on another, the second object applies an equal force on the first object but in the opposite direction. Each force in an action-reaction pair of forces is equal and acts in the opposite direction. But each force in the pair acts on a different object, so they are unbalanced forces. The action-reaction pairs in the diagram of the closed balloon are A1/B1 and A2/B2. You can be sure that two forces are action-reaction pairs if the objects in the description of one force can be interchanged to describe the other force. For example, “The gas inside the balloon pushes (force A) on the wall of the balloon. The wall of the balloon pushes (force B) on the gas inside.”
 
In the figure of the open balloon, only one pair of the identified action-reaction forces is present: A1/B1. With the balloon open, the force of the gas and the force of the balloon are unbalanced forces. So the gas does work (applies a force over a distance) on the balloon, causing it to move up. The work done by the gas on the balloon is equal to the energy (ability to do work) of the gas pushing on it. Energy of moving objects is called kinetic energy. Both work and energy equals the product of a force times the distance the force is applied. The energy and work of the gas on the balloon is equal to the energy and work done by the balloon on the gas. This work causes the gas to move down and out of the opening. With the balloon closed, neither the force of the gas nor the force of the balloon do work, meaning they don’t cause anything to move. This is because all the forces are balanced. Even so, the gas and the balloon have potential energy (stored energy).
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The same kinds of unbalanced forces make a rocket ship move. The gas inside the rocket pushes up on the rocket, and the rocket pushes the gas down and out. Aerospace engineers must consider the best size and shape to use in designing rockets that will produce just the right unbalanced forces.