3 17 science in our lives (space and technology)

In this book you have read about water mills and windmills2. Barnes/Stock Boston, BR ©Comstock Images/Getty Images; 6 ©Bill Varie/Corbis; 8 Getty Images; 9 BR ©Courtesy of JVC/DK Images

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by Ann Howard

Scott Foresman Science 3.17

Genre Comprehension Skill Text Features Science Content

• Call Outs

• Glossary

Technology

ISBN 0-328-13856-8

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Space and Technology

by Ann Howard

Scott Foresman Science 3.17

Genre Comprehension Skill Text Features Science Content

• Call Outs

• Glossary

Technology

ISBN 0-328-13856-8

ì<(sk$m)=bdifdb< +^-Ä-U-Ä-U

Space and Technology

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computer

invention

technology

tool

What did you learn?

1 What invention helped the Romans get water to

their cities?

2 How has modern technology changed kitchens?

3 Why are optical fibers better than wires?

4 In this book you have read about water mills and windmills Write to explain how each works Use examples from the book

water that goes into a hot water tank.

Illustrations: 4, 14, 18, 21 Robert Ulrich

Photographs: Every effort has been made to secure permission and provide appropriate credit for

photographic material The publisher deeply regrets any omission and pledges to correct errors called to its

attention in subsequent editions Unless otherwise acknowledged, all photographs are the property of Scott

Foresman, a division of Pearson Education Photo locators denoted as follows: Top (T), Center (C), Bottom

(B), Left (L), Right (R), Background (Bkgd).

Opener: ©Volvox/Index Stock Imagery; Title Page: ©Bill Varie/Corbis; 2 ©Dennis Degnan/Corbis; 3

©Mimmo Jodice/Corbis; 5 (TC) ©Billy E Barnes/Stock Boston, (BR) ©Comstock Images/Getty Images;

6 ©Bill Varie/Corbis; 8 Getty Images; 9 (BR) ©Courtesy of JVC/DK Images, (TR) Getty Images; 10 (CL)

NOAA, (CC) ©Time Life Pictures/Getty Images, (BR) ©Myrleen Ferguson Cate/PhotoEdit; 11 (B) ©Bob

Daemmrich/The Image Works, Inc., (CR) ©Stone/Getty Images; 12 (T) ©Jay Dickman/Corbis, (CR)

©Imperial War Museum/©DK Images; 13 (TL) ©Raymond Gehman/Corbis, (TR) ©ASAP Ltd./Index

Stock Imagery, (CC) ©Photodisc/Getty Images; 14 DK Images; 16 ©David Muench/Corbis; 17 ©Terry

Thompson/Panoramic Images; 18 ©Lester Lefkowitz/Corbis; 19 ©Terrence Moore/Woodfin Camp &

Associates; 20 ©The Image Bank/Getty Images; 22 ©Photodisc/Getty Images

ISBN: 0-328-13856-8

protected by Copyright and permission should be obtained from the publisher prior

to any prohibited reproduction, storage in a retrieval system, or transmission in any

form by any means, electronic, mechanical, photocopying, recording, or likewise For

information regarding permissions, write to: Permissions Department, Scott Foresman,

1900 East Lake Avenue, Glenview, Illinois 60025.

3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05

Science in Our Lives

by Ann Howard

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How does technology

affect our lives?

Finding New Ways

People always want to know how things work As

people learn things, they get new ideas People invent

tools to help A tool helps people do work more easily

or in a new way This means people use technology

Technology is using knowledge to design new tools

and new ways to do things Tools can be simple or

complicated

2

Arches were an important invention in ancient Rome An

invention is something made

for the first time The Romans needed water for their cities

They learned that arches with a central stone could hold heavy things They used these arches

to make bridges Bridges were used to move water to the cities

The keystone, or central stone wedged at the top, keeps the stones of the arch in place.

3

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Roofing and waterproofing

Electrical

Plumbing

Heating/cooling

Systems in a House

4

Technology in Your Home

Your home is made up of many parts These parts

form systems The systems must work together

What happens when you flush the toilet? You use

the plumbing system This system is made of faucets,

drains, sinks, and pipes These parts all work together

5

Some water in the plumbing system goes through a heater The electrical system is linked to it Electricity heats the water Together, the plumbing and electrical systems make it possible for you to take a hot shower

These air conditioners are part of a cooling system.

Can you find the parts that belong to each system in this house?

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How is a house built? Technology is used from the

beginning Boards are placed in very special ways

Builders know where to place boards to make a

house strong Each part must be put in the right

place to make a strong frame This is why planning

is important

Particle boards are used in walls The boards are made of wood chips Such wood chips used to be burned When burned, they caused pollution New technology turns those chips into strong boards that are used in walls

Wood chips are pressed and glued together to make particle boards.

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Technology Yesterday, Today, and Tomorrow

Two hundred years ago, kitchens did not have

electricity There was no refrigerator People had to

burn wood in a stove to cook food Cooking meals

could take all day

People began inventing new things First, ice boxes

were used to keep food cold Then, electric refrigerators

replaced ice boxes Today, microwave ovens cook food

in seconds Electric dishwashers wash dishes for you

The non-stick coating

on this pan was

invented in 1954.

Airtight seals for plastic bowls were invented in 1947.

9

In the past, people played records to listen to music

As a record spun, a metal needle moved along the grooves of the record Then a machine turned the vibrations from the needle into music Today’s DVD players use light beams to read the information

on computer-coded plastic discs Then a computer changes the information from the discs into images

on a screen

Some people think that computers will run your entire home in the future A refrigerator may be able

to order food when it becomes empty Technology may make this possible

Both CD and DVD players use light beams

The light beams play back the music and movies on the discs.

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Cameras in satellites

help in predicting

the weather.

Satellites can track cars on the road.

10

What are some

new technologies?

Tools for Extending Our Senses

Sailors once used math and the stars to find their

way Now they can use a Global Positioning System

(GPS) This system uses space satellites The satellites

send signals A ship’s GPS computer uses the signals

like a map Many cars today have a GPS

Satellites can be used in many other ways

Forecasters use pictures taken by satellites to predict

the weather

11

Tools for Processing Information

A computer stores, processes, and sends electronic

information very fast! Computer technology is all around you Computer chips are found in digital watches, cameras, and even cars

Optical fibers are making computers better These fibers are strands of bendable glass that carry light

The fibers are replacing copper wires in computer and telephone systems Optical fibers do not get hot, as wires do They also take up less space than wires They can even carry much more information

Optical fibers (right) are used

in communication systems now instead of copper wires (left).

Changing to new fiber optic technology requires a lot of work.

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Tools for Transporting Materials

Roads are important to us We use them to get to

school and to work We use them to transport goods

We use them to visit friends and family

The National Highway System is made up of

over 160,000 miles of highways These highways go

between the states in our country About 80 million

trucks haul supplies on these highways About 120

million cars move people from place to place

Highways were first built in the United States so military vehicles could move quickly.

Highway engineers

design roads such as the

ones pictured above.

13

Roads are not the only way of moving people and things People and freight are moved using trains and planes too

But rivers were the first transportation system in the United States Rivers are still full of boats moving goods today Technology will always keep things moving!

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Unexpected Uses

Technology uses are not always planned The

microwave oven is a good example In 1946 Percy

Spencer was working to improve radar He was testing

a light bulb The bulb used microwave energy

One day, Spencer stood by the tube A candy bar

in his pocket melted Spencer then placed popcorn

kernels near the microwave energy They popped

Spencer discovered that microwaves could cook foods

fast! Soon, the microwave oven was invented

This is Percy Spencer’s

design of how a microwave

oven would work.

Magnetron

Wave guide Food to be

cooked

Flat LCD screens take up less space than older glass screens.

15

Do you watch TV? Glass tubes were used to show the picture in early television sets and computers But these tubes were big and heavy With new technology, screens are light in weight The LCD screen was

invented in 1970 by James Fergason LCD stands for liquid crystal display Liquid crystals control the flow

of light This makes an image on the screen These screens do not need heavy glass tubes They are also flat in shape So they take up less space

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How does technology

help us get energy?

Using Energy

Put in a DVD Heat up a snack in the microwave

Just be sure everything is plugged in! None of this

would be possible without electricity

Before electricity, people used energy from wind and

water Water-powered mills were built near rivers The

force of flowing water turned a wheel At a sawmill,

the wheel turned rods, gears, and belts This powered

saws that cut wood

17

Windmills were also used to do work Windmills use wind for power Turning blades move gears in a box

Energy in the gears moves a rod up and down This can be used to pump water from under the ground

There are good and bad things about using windmills and water mills Both wind and water are renewable sources of energy They do not cause pollution But they don’t make enough power for all our needs

Windmills use wind

to pump water.

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Producing Electricity

Waterwheel technology is still used in hydroelectric

power dams These dams are built on rivers Water in

lakes behind the dams stores potential energy To free

this energy, gates let water into a power station The

flowing water spins the blades of a waterwheel in a

turbine The kinetic energy of water is changed into

electricity in a generator People use the electricity

for power

This generator can change the kinetic energy of flowing water into electricity.

Connected to each generator is a turbine The energy

of moving water spins the blades in the turbine.

19

Hydroelectric power does not make much pollution But the lakes behind dams can cause flooding

There are other ways to make electricity One way is

by burning coal, oil, or natural gas The heat created

is used to boil water The boiling water makes steam

Pressure from the steam turns wheels in electricity generators

This technology makes plenty of electricity But it also creates the problem of air pollution

Hoover Dam is one of the largest dams in the world.

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Future Sources of Energy

Our need for energy keeps growing How will we

keep meeting this need?

Solar energy may be one answer This energy comes

from sunlight Special panels collect sunlight Each

panel has lots of small solar cells They change energy

from the Sun into electricity Solar energy is common

in deserts The Sun shines there much of the time

Solar panels collect the Sun’s rays.

Solar energy heats the water held in this appliance.

21

Thanks to new technology, solar energy costs less

People can buy panels to put on their roofs But these panels make hot water, not electricity

Here’s how it works First, water runs through small tubes Next, the Sun’s rays are changed into heat This happens when the panels absorb the rays Then the heat warms the water in the tubes Finally, the hot water flows into a tank It is stored until it is used

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Wind energy is helping too Windmills are put in

places that get strong winds Huge blades change the

kinetic energy of wind into electrical energy

Computers are used to tell when wind conditions

have changed Motors then adjust the direction and

angle of the blades This way, electricity is made

whenever strong winds blow

22

Windmill blade wheels can be

wider than a football field is long!

Technology makes new ways of creating electricity possible It also helps the systems in your home to work together Technology helps us every day It has changed our lives in many ways Who knows how technology will change our lives in the future

23

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Glossary

sends electronic information quickly

technology the use of knowledge to make new

tools and new ways to do things

more easily

Vocabulary

computer

invention

technology

tool

What did you learn?

1 What invention helped the Romans get water to

their cities?

2 How has modern technology changed kitchens?

3 Why are optical fibers better than wires?

4 In this book you have read about water mills and windmills Write to explain how each works Use examples from the book

water that goes into a hot water tank.

Illustrations: 4, 14, 18, 21 Robert Ulrich

Photographs: Every effort has been made to secure permission and provide appropriate credit for

photographic material The publisher deeply regrets any omission and pledges to correct errors called to its

attention in subsequent editions Unless otherwise acknowledged, all photographs are the property of Scott

Foresman, a division of Pearson Education Photo locators denoted as follows: Top (T), Center (C), Bottom

(B), Left (L), Right (R), Background (Bkgd).

ISBN: 0-328-13856-8

protected by Copyright and permission should be obtained from the publisher prior

to any prohibited reproduction, storage in a retrieval system, or transmission in any

form by any means, electronic, mechanical, photocopying, recording, or likewise For

information regarding permissions, write to: Permissions Department, Scott Foresman,

1900 East Lake Avenue, Glenview, Illinois 60025.

3 4 5 6 7 8 9 10 V010 13 12 11 10 09 08 07 06 05

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