Name Pd [)ate

MarginNotes!

Collectinq Weather t)ata 0

* Part 1 Directions: Read and write margin notes.J%

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1 The conditions of the atmosphere at a certain time and place are called wealher. rs weatherimportant in your Iife? It affects what clothes you wear and your choices of activities. It may evenaffect your mood. The weather of an area is due to four factors. They are heat energy, air pressure,winds, and moisture. Changes in these factors determine the kind of weather an area will have. Webase decisions on wha+ to wear, where to go, and what to do on the weather forecast.

2 To make weather maps and foraecast weather, weather data must be collected from Earth'ssurface and atmosphere. Scientists analyze the weather maps and the data in them to forecast theweather. These data are collected in many ways. Data comes from a Latin word meaning "somethinggiven." It is the plural form of the word "datum." Today, we often use it as both singular (meaningiriformation) and plural (meaning facts or pieces of information).

3 [)ata are collected at weather stations on the ground. More than four hundred natiorial weatherstations in the United Slales measure weather conditions many times every day. Each stationmeasures weather conditions such as temperature, atmospheric pressure, wind speed and direction,amount of cloud cover, and precipitation. The National Weather Service uses the data to makeweather maps.

4 Radar is another tool meteorologists use to gather data. Radar, which stands for radio detectingand ranging, sends out radio signals that are reflecled from objects such as clouds and rain.Compulers turn the reflections into images. Radar on ground Ievel is used fo identify areas of heavy,medium, or low precipitation. You have probably seen radar images on television. They usually appear indifferent colors to show different amounts of precipitation.

s 0ne of the most valuable sources of global weather information is weather satellites. A sa+elliteis a body in orbit around another Iarger body. The moon is a natural satellite of Earth. But Earth hasmany man-made satellites in orbit around it. The satellife's speed and momentum keep it from fallirig,and Earth's gravity keeps the satellite from flying off into space.

6 Weather satellites orbiting high above Earth's surface take images of cloud patterns and stormsyaAems and can track their movements. You often see such pictures on television weatherbroadcasts. Weather satellites also record data about wirids, temperature, rainfall, water vapor, waveheight, soil moisture, and snow cover.

7 AAosl satellites are either polar-orbiting or geostationary. Polar-orbiting satellites circle theglobe in a north-south orbit crossing over the poles and the equator. They are called "Iow Earth orbif"satellites because they orbit only about five hundred miles above Earth's surface. Because of Earth'srotation, polar-orbiting satellites cover different parts of Earth from one orbit to the riext. Theyhave heat sensors that measure the temperatures of the oceans, the Iand, the air, arid the clouds.The National Weather Service uses this information to forecast weather for days and even weeksahead. This information also helps scienlis'fs study how the climate is changing over long periods oftime.

8 Geostationary satellites complete one orbit, traveling easl to west, in the same time it takesEarth to rotate once. They musf be at high altitudes to be able to do this. They are called "high

Earth-orbit" satellites because they orbit more than 22,000 miles above Earth. Becausegeostationary satellites rotate with Earth, lhey're always above the same spot on Earth's surface.This means that they monitor weather conditions over the same area. They cart take picturescoritinuously of storms forming over Iand and oceans. The newest geostationary satellites can collectinformation from inside hurricanes, recording wave heights, surface winds, and rainfall. 5ome nowcarry microwave sensors that can gather information through cloud cover.

9 As technology improves, weather forecasters will have better knowledge to allow them to predictweather with more accuracy. This will help save Iives and decrease property damage in cases ofsevere weather such as hurricanes and typhoons.

By cindy Grigg

Part 2 Directions: Ariswer the questions,

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1. The weather of an area is due to what four faclors?

A. Heat, gravity, magnetism, and windsB. Volcanoes, humidity, the sun, arid the windC. Heat energy, air pressure, wirids, arid moisture

2. Name three ways weather data are collected.

A. Rain gauges, thermometers, and wind socksB. People, computers, and radarC. Ground weather stations, radar, and weather satellites

3. The National Weather Service uses the data collected to:

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A. Name hurricaries

B. Launch weather safellifes

C. Make weather maps

4. In weather forecasting, radar is used to:

A. Identify areas of high and Iow temperaturesB. Identify areas of heavy, medium, or Iow precipitationC, Identify wind speeds

s. Which type of satellite orbits at a higher altitude?

A.GeoslalioriaryB. Polar-orbiting

6. Why do you think it is important to collect weather data? Which type of data collecfion do youthink is more important?

Name Pd Date

Newton's Three Laws of Motion &Part I Directions: Read the article.

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1 Isaac Newton was born in 1643. His family was wealthy, so in some ways he had advantages over otherkids his age, but in other ways he was disadvantaged. Isaac's father had died before Isaac was born, and hewas raised by his grandmother and other relatives. At first he probably was not encouraged to Iearn much inschool. He didn't pay attention in school, and was described as Iazy. It was only after an uncle encouraged himto prepare to go on to college that he began to take an interest in school arid to develop his talents. One ofthe skills he developed while still in school was making model machines, including clocks and windmills. Incollege he begari studying the Iatest theories in math. Soon he was coming up with theories of his own, andtoday Sir Isaac Newton is well known for his three Iaws of motion as well as for other scientificbreakthroughs.

2 Here are Sir Isaac Newlon's three Iaws of motion.

3 Law 1- An object moving in a straight Iine will continue moving in a straight Iine, unless acted on by anoutside force. Also, an object at resl will stay at resl. The word for this is inertia.

4 Law 2 - Force will cause a change in the motion of an object. The change in motion depends on the amountof force and the mass of the object. There is a formula for this F:ma (force equals mass times acceleration).

s Law 3 - For each action, there is an equal and opposite reaction.

6 These three laws will make more sense, and be a Iot more iriteresting, if you do some experiments todemonslrale each law. Maybe Sir Isaac did some similar experiments when he was testing out his lheories.

7 To demonstrate the firaA Iaw, you might want to try the old trick of pulling the tablecloth out fromurider +he dishes on the table. If you do it just right, you will remove the table cloth without causing thedishes to crash to the floor. Then again, maybe you wouldn't wanf to try that one, even though Newton'sfirst Iaw says that ob:3ecls at resl, Iike the dishes, will stay at rest.

8 Another way to demonstrate inertia is to show what can happen when you don't wear your seat belt. Asafe way to demonstrate this is wifh a small toy truck, a clay figure, a ramp, and a brick. Place the Iittle clayfigure in the toy fruck. Place the brick just a short distance past the end of the ramp. The toy truck can rolldown the ramp until it hits the brick. When it hits the brick, the truck will stop suddenly, but the clay figurewill keep moving forward and fly out of the truck because of inertia.

9 For the second Iaw, there are many demonstrations that you can do. Anything that involves using a forceto move an object would demons+rafe Newton's secorid Iaw. You might want to try an experiment tri which youchange the amount of force that you use, or change the mass of the ob3ecls that you try to move. Forexample, you could set up a Iittle seesaw, made from a ruler balanced on a pencil. Try objects of differentweights at the one end, and drop something on the other end +o see which ob3ecl moves the farthest. Or, trydropping the objects from different heights.

10 The third Iaw is fun to demonstrate. One way is with a basketball and roller skates. Two kids, eachwearing roller skates, stand facing each other and throw a basketball back and forth, As each kid pushes thebasketball forward, he will roll backwards on his skates. That is the equal and opposite reaction described inthe third law. You can also build a balloon racer to demonstrate the third Iaw. Tie a string between two

chairs, pretty far apart. Put an empty pen case or a section of a straw on the string so that it can slide alorigthe string. Now blow up a balloon but don't tie it. Carefully tape the balloon to the pen case or straw, then letgo. The action of the air shooting out of the balloon causes a reaction of the balloon racing across the stringtowards the opposite end.

11 If you don't feel Iike doing experiments, you can always observe Newton's Iaws of motion in anotherIocation, an amusement park. Roller coaslers, merry-go-rourids, and bumper cars all follow Newton's threelaws of motion, and are part of the science of force and motion.

By Sharon Fabian

Part 2 Direc+ions: Answer the questions.

1. Sir Isaac Newton's only discovery was the three Iaws of motion.True

False

2, According to the first Iaw, an object that is sitting still will stay that way.True

False

3, The formula F=ma means "force equals motion times acceleration."True

False

4, The third law says that some actions will produce an equal and opposite reaction.True

False

s. 5ir Isaac Newton probably never conducted any experiments.True

False

6. One word that sums up the first Iaw isA. Motion

B. Acceleration

C. Inertia

D. Force

7. Bumper cars are an example of Newton's third Iaw. Explain.

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8. A roller coaster is a good example of more than one of Newlori's Iaws of motion. Explain.

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Forms of Energy

Directions Part 1: Read and highlight the article

Energy is power - the ability to do work. Parents, teachers, and babysitters often feel drainedof energy as they chase young "bundles of energy!" But, energy is not just the ability of a person tomove and work and play. Every time anything moves - the wirid, waler, cars, clocks, ariimals, andmore - energy is what makes it happeri! All movement is energy.

1

2 Energy makes your remote control cars, radios, video games, and computers work. Energy makesplants arid animals grow. It takes energy to cook a meal or read a book! We use energy every day.

3 Nothing can run well on an empty tank, not a car nor a plane nor even our bodies! We need fuelso that we will have the energy to work and play. Our fuel is food. Food is where we get our eriergy.The energy in food is called calories. [CAL-uh-reez? We take in calories by eating and drinking, andwe use calories by moving. The more you move, the more calories you burn. Yoi.ir body even burnscalories when you are asleep, but not very many.

4 Your body only needs a certain amount of calories each day. If you take in more calories thanyou need, your body will slore it. 51ored calories are energy waiting to be needed. It is called fat.Everyone has slored fat in their bodies, some more than others. You need some fat; people whodon't have enough fat are often not healthy, 3usl like people who have too much.

s It is also not healthy to skip meals. You should fill your "tank" at least three times a day. Makesure to include fruits and vegetables in your "fuel" and you will have plenty of energy!

Brenda B. Coverl

Directions Part 2: Read the question and circle the correcl ariswer

1. Energyis: '2. Caloriesare:A. Food A. Light bulbsB. 5hape B. Eriergy in foodC. Big C. Fat cows

D. Povver [). Burning candles

3. You burri calories in your sleep.True

False

-5. Fat is:

A, Stored sleepB. 5tored energyC. Bad

f). Calories

All movement is:

A. Slow

B. Energy

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C. Fast

f). Dance

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ll 4. It is not healthy to:

A. [)rink waler

B. skip mealsC. Count calories

[). Eat apples

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Name Pd Date

The Periodic Table

Part 1 f)irections: Qead the article.

1 People have always tried to organize things. Organizing things helpsus to understand them and to see how different things are related.Maybe you have noticed your Iittle brother or siaAer grouping toys or blocks by their color or size. Ancientpeople had their own ways of organizing things. The ancient Greeks suggested that everything in the worldcould be organized into four groups-earth, wind, fire, and water. Today, scientists generally organize theworld into two main groups, matter and energy. These main groups are then organized some more into smallergroups.

2 Today we use the periodic table to organize matter. It is a chart that shows all of the basic elements thatmake up our world organized into rows, called periods, and columns, called groups.

3 It fook a long time before we came up with this arrangement, though! Scientists tried a Iot ofarrangements before they came up with one that worked. Dr. Timmothy Slowe created a chart of the elementsthat was made up of zigzag rows. Professor Theodore Benfey's chart looked like a circle with three bighandles. Emil Zmaczynski drew a triangular chart.

4 In 1869, [)mitri Mendeleev crealed a periodic table much Iike the orie that we use today, He arranged theelements in groups and periods to show the relationships between the elements. One amazing thing about hisperiodic table was that it Ieft blank spaces for elements that would not be discovered until much Iater! That iswhy the periodic table that we use today, over 130 years Iater, is still so much Iike Mendeleev's original one.

s The periodic table is made up of squares, with each square representing one element. There is a square forcopper, a square for oxygen, a square for neon, and so on. To help understand the periodic table, Iet's look atjust one square. Take a piece of scrap paper and draw a square. In the center of the square, write "He." At thetop write the number 2. At the bottom, write the number 4.003. The le'hers in fhe middle are the symbol forthe element. Usually, it Iooks like an abbreviation for the element's name, but not always. These symbols areinternational; they are used all over the world. "He" stands for helium. The number at the top is the element'satomic number. It tells the number of prolons that that element has. This is also the number of eleclrons,since atoms have the same number of protons and electrons. Helium has two protons and two electrons. Thenumber at the bottom is the mass riumber. It is usually written as a decimal number, because it is the averageof the mass numbers of different forms of the element. The mass number tells how heavy an atom is, and it isthe total of its protons and neutrons. Helium has a mass number of about four, so we kriow that it has twoneutrons and two protons.

6 The periodic table is just one of the tools that scientists use to make discoveries about the elements. Oneinteresting thing about helium is that it was discovered in a solar eclipse. You probably know that helium is usedin balloons, but did you know that it is also used in pressurized rocket fuel, and to cool nuclear reactors?

7 If you know how the periodic table is arranged, you can tell a Iot about an element just by where it isIocated on the table. For instance, the elements on the left side are metals. The elements on the right side arenorimetals.

8 Elements are arranged in order by their atomic numbers, so the elements at the top of the table areusually the Iight weight ones. Hydrogen, at number orie, is lighter than air, Radon, at atomic number 86, is a

heavy gas. There are safety concerns about radon gas, and since it is heavy, people know to search for it in thebasement of homes, not in the attic.

9 There is a Iot more that the periodic table can tell us. To start learning about the elements, you mightwant to make some flash cards to Iearn the name and symbol for each element. You can play a game ofconcentration with the flash cards. Then take some time to study the periodic table itself. You should be ableto find web sites with some good information about it. See what conriections you can discover between thedifferent elements.

By Sharon Fabian

Par+ 2 Directions: Answer the questioris, 16

1, The periodic table isA. A chart

B. A book

C. A piece of furnitureD. An element

2. Today's periodic table was irivented byA. Bill NyeB. Dr. Slowe

C. Dmitri Mendeleev

D. Ancient Greeks

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3. Which of the following describes the modern periodic table?

A. A chart made of zigzag IinesB. A chart made of rows and columns

C. A square[). A triangle

4. Radon and helium are nonmetals. They would be on the of the periodic table.

A.TopB. Left side

C. Right side[). Bottom

s, Iron and copper would be on the of the periodic table.

A, Right sideB. Left side

C. Bottom

0.Top

6. Today's periodic table is much Iike the one Mendeleev drew in 1869. It has not changed much because

A. Mendeleev left spaces for the elements that had not been discovered yetB. No new elements have been discoyered

C. All of the new elements are just added on at the end of the tableD. Mendeleev made a lucky guess

Forces

Part 1 birections: Read the article.

Name Pd Date

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1 What is a force? A force is a push or a pull. Forces are acting all around you. Forces are even acting on you!Ob:3ecls (and you) are being pushed and pulled in different directions. Sometimes the force can be seen, likewhen you push a toy car or throw a ball. Somefimes you don' t see forces at all. Even objects that are notmoving have forces acting on them. Forces have the ability to cause change.

2 Forces always come in pairs. Ob:3ecls exert forces on each other. Wheri you run into something, lel's sayanother person, you exert a force on that persori. He may fall down if the force is strorig enough. But thatother person also exerls a force ori you. You might also fall down. You can see movemerit caused by the force.If you run into a wall, you might not see any movement. The wall doesn't move. You probably wouldn't fall down.But it might hurt. You pushed on the wall, or exerled a force on the wall. The wall exerted a force back on you.It hurts the part of your body that hit the wall because the wall exerled a force on your body.

3 The strength of the force is called the magnitude of the force. Forces also have a certain direcfion. Forexample, when you are standing, you exert a force on the ground that is equal to your weight. Your body isexerting a force on the ground in a downward direction.

4 Forces are measured in uriits called newtons. Newtons were named for the English scientist Isaac Newlonwho came up with the set of Iaws that describes forces and motion. It takes about forty newtons to Iift a smalldog.

s Forces can affect objects in several ways. Forces that act on an object that is not moving can cause theobject to move. Forces can act on an object that is already moving to cause a change in the object's speed ordirection of movement. A force can act on an object and not make it move. Forces acting on a still object canchange the object's shape. For example, if you sit on a bean bag chair, you can see how the force of your bodypushing dowri on the chair changes the shape of the chair.

6 Acceleration means a change in the speed or direction of an object. When something speeds up, we saythat is a positive acceleration. When it slows down, we say that is a negative acceleration. But remember thatacceleration can also be a change in the direction of an object that is moving. An object that is moving along acurved path is always accelerating. That is to say, its Iine of motion is always changing.

7 The force you are probably most familiar with is the force of gravity. Gravity is the force of attractionbetween ob:3ects that have mass, Two ob:3ecls that have mass are attracted toward each other. They exerlforce on each other. They pull on each olher. Hold a book out from your side and let go. What happens to thebook? It falls until it hits the floor. What force pulled on the book? The force of gravity. The book and theearth are attracted to each olher. Earth pulled the book toward its center.

8 Mass is a measure of the amount of "stuff" in an object. Since all objects have mass, gravity acts on allob:3ecls. You know that the earth pulls all objects toward its center. But what you might not know is that allob:3ecls, including you, pull the earth toward their centers. Since the earth is a Iot bigger than you, it pulls a Iotharder on you than you pull on it.

9 The greater the mass of either of two ob:3ecls, the slronger the force of gravity is between them. Theforce of gravity belween the earth and the book you Iet go of is slronger fhan the force of gravity betweenyour hand and the book. The earth, because it has so much more mass, pulls more on the book thari your handdoes. That explains why the book falls when you Iet go of it, and it doesn't stick to your hand.

10 The strength of the force of gravity depends on two things, Orie is the mass of the two ob:3ecls. Theother is the distance between the two things. The closer the two ob:3ecls are, the slronger the force. Thefarther apart the ob3ecls, the weaker the force exerted by the objects on each olher.

11 For example, the sun and the moon both exerl gravity on the earth's oceans, This is what causes oceantides to rise and fall. The sun is about 400 times bigger than the moon. But the moon is much closer to theearth. So the moon exerts more force on tides than the sun does.

12 Forces are all around you. Uriderstanding forces helps us understand how marry things happeri. Physics isthe branch of science that studies forces, eriergy, and motion. Every motion you make and every job you douses forces.

By Cindy Grigg

Part 2 bireclions: Seled the correct answer.

1. A jorce is a:

A, Push or a pullB. Strange, unknown powerC. Field of energy around something

2. Forces have the ability to:A. Be seeri

B. Be invisible

C. Cause change[). All of the above

E. None of the above

3. Forces can act on an object and:A. Cause the object to moveB. Cause a change in the speed of the objectC. Cause a change in the direction the object is movingD. Cause a change in the shape of the objectE. All of the above

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4. What is magnitude?A. The height of the ob:3eclB. The strength or amourit of the forceC. The attitude of a force

s. Forces are measured in units called:

A. Newtons

B. MagnitudeC. Pounds

D. Kilograms6. Acceleration is:

A. Speeding up of an objectB. Slowing down of an objectC. Change in the direction of a moving ob:3ectD. All of the above

7. When you lhrow a ball, what happens? Can you explain what two forces act on the ball?

Name Pd Date

MarginNotes

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Our Solar System

f)irecfions Part 1: Read the article. Take margiri riotes.

Our solar system has many parts. The solar system ismade of our suri and everythirig that orbits around it. Thisiricludes the planets and their moons. It also includesasteroids, meteors, and comels. These things are held inorbit by the suri's gravity.

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2 There used to be riirie planets. Pluto used to be called aplanet, too. But scientists have decided that Pluto isri'treally a plariet at all. Now our solar system has eight planets.They are Mercury, Venus, Earth, Mars, Jupiter, Saturri, Uranus, and Nepturie.They are listed in order by their distarice from the sun.

3 Some of our plariets have moons, or satellites, that orbit the plariet. Earthhas orie moori. J upiter and several other plariets have marry mooris. Mercury aridVerius dori't have any moons.

4 Plariets move two ways. They move arourid the sun in almost circular orbits.The olher way they move is that they rotate. This means they spin around ori animagiriary axis like a top. It takes Earth orie year to complete its orbit arouridthe suri, or make orie revolutiori around the suri. It takes Earth orie day to rotateori its axis,

s Four of the plariets are larger thari Earth. They are Jupiter, Saturn,Urarius, arid Neptune, Three of the plariets are smaller than Earth, They areVerius, Mars, arid Mercury. Venus is orily a little smaller thari Earth.

6 Betweeri Mars and Jupiter lies art asteroid belt, This is an area coritainirigmany asteroids. Asteroids are large churiks of rock arid metal. Pieces ofasteroids that break off are called meteors. Comets orbit the sun, too. Comelsare big churiks of ice, gas, arid dust. Sometimes they are called "dirtysriowballs."

7 Scieritists who study our solar system use big telescopes. There have beenseveral space probes sent to jake pictures of most of the planets. There is artIriterriational Space Station, called the ?55, where astroriauts live and work inspace for several months at a time. It seems the more people study space, themore they warit to learri.

By Ciridy Grigg

Directions Part 2: Ariswer the questions

1. What is tri the solar system?(A? The sun and everythirigthat orbits around it

(X> Planets and their mooris

. Asleroids and comets

(X> All of the above

-3-.???'Ho-w rr3. How marry planets are in the solarsystem?. Six

. Five

. Severi

. Eight

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4. Which plariet is almost the same sizeas Earth?

. Jupiter

. Mercury

. Verius

. Mars

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2. What keeps the planets tri orbit?. The suri's gravity. The moon's gravity. The planets' gravity

s. are called dirty sriowballs,

7. Another word for "moori" is

(K> Plariet

(X> Iriterriational SpaceStatiori

(D Satellite

(X> Space shuttle

6. How do we kriow about the other

plariets?. We have traveled to the olher

planets.(X> Telescopes, space probes,and the Iriterriatiorial SpaceStatiori

i (? We are only guessing.

, 18. Plarietsmoveirihowmariyways?(X> They move tri orie way.(X> They dori't moVe at all,(l> They move tri two ways.(X> They moVe tri threediffererit ways.

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Wrife a summary of the things you know about the solar system.

Name Pd [)ate

Eureka! Density!

Directioris Part 1 : Read and highlight the article

What is density? [)ensity is simply the amount of "stuff" in a given space.r m

Scientists measure density by dividing the mass of something by its volume (d :m/v). This is a slory about how the concept of density was firsl "discovered."

It is the slory of a Greek mathematician named Archimedes who livedaround 250 B.C. The King of Syracuse, where Archimedes lived, thought that hewas being cheated by the metal craftsman who made his golden crown. The Kingcalled Archimedes to him and gave him the task of finding out whether thecraftsman had replaced some of the gold in the King's crown with silver. 5ilver was worth less moneythan gold, and it also was an insult to the King to be wearing a crown that was not pure gold.

1

2

3 The King gave Archimedes some rules. Archimedes could not damage the crown in any way. He couldnot melt down the crown to see if it was made of other metals. He could not scratch the crown to see if

there was silver underneath the golden outside. Archimedes thought about the problem while taking abath. As he entered the bathing pool, he noticed that water spilled over the sides of the pool. Herealized that the amount of water that spilled was equal in volume to the space that his body occupied.This fact suddenly provided him with a method for finding out if the King's crowri was made of pure gold.

4 Archimedes knew that silver is not as "heavy" as gold. (Actually, silver has less density than gold.)Because an amount of silver occupies more space than an equivalent amount of gold, Archimedes placedthe craftsman's crown and a pure gold crowri of the same mass in two tubs of water. He found that morewater spilled over the sides of the tub when the craftsman's crown was submerged. It turried out thatthe craftsman had been cheating the King! Legend has it that Archimedes was so excited about hisdiscovery that he ran naked through the slreels of 5yracuse shouting "Eureka! Eureka!" which is theGreek word for 'T have found it!"

s When Archimedes stepped into his bathing pool, not only did he realize that water spilled over theedges, but he also noticed something that we all notice when we go swimming - he felt lighter. The abilityof an object to float wheri it is placed in a liquid is called buoyancy, and it is related to derisity. If anobjecl is Iess derise than the liquid in which it is placed, it will float on the liquid. If it is denser than theliquid, it will sirik.

6 For example, wood floats on water because it is Iess dense. 5teel sinks because it is denser thanwater. How can large sleel ships float? Large ships have a tremendous amount of space in them that isfilled with air. The cabins, halls, and dining room are all filled with air. While steel is denser than water,air is less derise. Metal ships can float because their total density is less than that of the water thatthey float on. When the Titanic struck an iceberg, waler rushed in and replaced the air in the ship's hull.As a result, the total density of the ship changed and caused the ship to sink.

7 Archimedes had a problem to solve. He came up with a hypothesis based upori his observatioris, andhe found a way to test his hypothesis, Archimedes used the scientific method to solve the Kirig's

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problem. Archimedes also used what he kriew and applied it to his problem. This is the basis for allscience. You can be a scientist like Archimedes, too!

By Cindy Grigg ei-.'A-?)/ l

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0irections Part 2: Circle the correct answer to the questions.

ho "discovered" the coricept of density?Cialileo

B. pristoile

C. Archimedes

[). Ptolemy

3. Where did Archimedes Iive?

A, New York

B. Rome

C. Frarice

0. Cireece

s. How did Archimedes find the truth?

A. He weighed the crowris.B. He put lwo crowns in waler and saw whichone displaced more water.C. He took a bath.

[). He melted the crowns.

7. If an ob:3ecl is less dense than the Iiquid it isput into, it willA. 5hine

B, Sink

C. Float

D. Melt

'2, About how Iong ago did Archimedes Iive?A. 2,000,000 years agoB. 2,260 years agoC. 250 years ago

'? 0. 2,00;O years agol.4. What did the King want Archimedes to do?

A. Find gold.l

B. Find out if the crown was pure gold.

I C. Find out if the craftsman had cheated him.

[). Both B and C

6. What does "Eureka!" mean?

A. I have forgollen my clothes!B. I have found it!

C. I have lost it!

[). I have saved the King!

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8. If an ob:3ecl has a higher density than theIiquid it is put into, it willA. Float

B. Melt

C. Shine

[), 5ink

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Directions Part 3: Explain, in complete sentences, what density is.

Name Pd Date

Simple Machines

t)irections Part 1: Read arid highlight the article

Machines make work easier. When a caveman had to move a rock that was loo heavy tolift, he might have used a big stick to make it easier. A long, long time ago, someoneinvented the wheel, and that made things a lot easier. By the Industrial Age, people were {,3 .inventing all kinds of machines. New vehicles and riew faclory machines made life easier andgave people free time that we never had before. We really Iiked these iriventions that madeour lives easier! People are still creating new machines all the time. There is somethingreally fun about inventing a contraption that seems to do some of our work for us.

1

2 Machines make work easier. So to understand machines, you firsl have to know what the work is,scientifically speaking. Maybe you define work as carrying out the garbage, raking Ieaves, or cleaning yourroom. These are all forms of work, but scientists have a more, well, scientific definition. To them, work is

using a force to move an ob:3ecl across a distance.

3 There is a mathematical formula for this: W : F x O. It means "work equals force times distance."

4 Machines make it possible to move larger ob:3ecls, or to move objects fasler or farther. Machinesmake work easier by adjusting the force or the distance to your advantage. They are used to push, pull,and lift. A machine can be used to increase the force or the distance, but not both. To get more force, youhave to give up some distance. To get more distance, you have to give up some force. It's a scientific lawcalled Conservatiori of Energy.

s Machines let you do more with less muscle power, When a machine is used to increase force, that iscalled mechanical advantage. For example a :3ack used to Iift a car has a Iot of mechanical advantage. 5odoes a crane used to lift a heavy steel beam. A hammer used to pound in a nail has mechanical advantagetoo.

6 While there are probably loo many kinds of machines to count, many of them are really justcombinations of six basic machines. These are called the six simple machiries. They are the inclined plane,Iever, wedge, screw, wheel and axle, and the pulley. Here are a few examples:

7 inclined plane - the sliding board on the playground

8 Iever - your snow shovel

9 wedge - an axe for splitting logs

10 screw - nuts and bolts to fasten things together

11 wheel and axle - on your favorite sporls car or little red wagon

12 pulley - at the top of the flag pole

14 Of course these six machines were all invented a while ago. The machines being invented now arecomplex machiries, or combinations of more than orie simple machine. If you've ever takeri apart an oldclock or a loasler, you know what a complex machine Iooks like. A Mousetrap game is a neat example oflots of simple machiries workirig logether, even though it doesn't really make the job of catching thatmouse any easier! The next time you play Mousetrap, see how many simple machines you can identify.

By Sharon Fabian

pirections Part 2: Answer the questions

1. A snow shovel is an example of a(n)A, Inclined planeB. Lever

C. Pulley[). Wedge

All possible machines have now been invented. 4. One machine can increase both the force and. 7alse distance at the same time.

. True . (alse

- True

s. Complex machines are combinations of more 1,6. "Work equals force times distance" can bethat one simple machine.

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written

l . False A,W=FxD

. .True B.W:F-D

C.W=F*9

D.W=F/t)

2. A large stick used to move a heavy rock is asimple machine.- False

. True

3.

7. What kind of simple machines are the blades of 8.a pair of scissors?

What kind of simple machines might you findinside of a clock (the old fashioned kind withhands)?

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Thl #? 'Directions Part 1: Read the article

Key Name Pd Date

5ome of the best inventions happen by accident, like Toll House cookies. However, most inventionshappen af?ter many years of research. Scientists test and retest ideas hoping to solve scientific puzzles. Goodscientists use a process called the scientific method.

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2 The scientific method is a series of problem solving steps that help scientists answer scientific questions.You also use the scientific method when you work on experiments in your classroom. 5cientists use thismethod to prove or disprove a scientific question. These questions usually are asked after scientists havemade observations. An observation happens when you use your serises to riotice your environment. Forexample, as you leave for school, you notice that your mildly curly hair became very curly (almost frizzy) assoon as you walked out of the door. You are not happy about this development, since it took you a long time toget your hairdo just right. Although annoying, this is an observation.

3 After observing your high hair, you ask yourself, "Why does my hair become very curly when I stepoutside?" This is your scientific question. You slarl to guess or think about possible reasoris for your frizzyhair. The time has come for you to make a good guess or a hypothesis based on your observations. You predictthat your hair becomes very curly because of the humidity in the air. To prove your hypothesis, you need todevelop a procedure or plan to test your prediction.

4 Your plan is very simple. 5ince you heard on the news that the humidity would be high tomorrow, youdecide to (1) do your hair again and (2) step outside the door and see what happens. These two steps will allowyou to see if humidity causes mildly curly hair to become curlier. When you wake up in the morning, you gothrough your usual hair routine. When you step outside, you are not disappointed because your hair becomeseven curlier today since the humidity is even higher. Now you are ready to record your results.

s Scientists record their results either with pictures or with words. They use charts, graphs, diagrams, aridsummaries to communicate their results. In this case, you may wish to mentally note what happens to your hairon humid days. You might also choose to share the results or data with your friends at the lunch table inschool. You could also wrile a short paragraph about your experiment and give it to your teacher. However,before you record your resulls make sure you iriclude a conclusion. This conclusion or statement tells theresulls of your experiment. Yoi.ir conclusion is, "When people with curly hair walk outside on humid days, theirhair may become curlier depending on the amount of humidity."

6 You are probably feelirig good about your results and think that your scientific study is over. However,good scientists also ask more questions, record more observations, and offer more suggeslioris about the

subject they are studying. You may ask, "Is there a way to prevent my hair from becoming curlier or frizzy onhumid days?" Afler researching your new question, you could offer si.iggeslioris to other people with yoi.irdilemma. Keep in mind, that whatever scientists investigate, they know that the scientific method is the keyto unlocking scieritific secrels.

By Trista L. Pollard

Directions Part 2: Complete the questioris below.

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1. A hypothesis isA, A prediction or guess that is notbased on observations

B, A prediction or guess based onobservations

C. A result of an experiment[). None of the above

3- What is an observation?

5- What is a conclusion?

2, The scientific method is one stepscierilisls use to solve scientific

problems.False

True

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4- Which statement is not a

prediction?A. I think the salt will dissolve when

I add water to the cup.B. I think I will stay home tonight.C. I think the balloon will pop whenthe chemicals react.

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[). I think the wood will float when I

put it into the water. lWhen a person with curly hair goes 'outside on a very humid day, nothinghappens to the person's hair.False

True

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t'A Name Pd Date

What Ooes an Astronomer t)o?

Part 1. Direcfions: Read and highlight important information in the article.

1 Aslroriomers study planets and the sun in our own solar syslem, as well as other stars, solar syslems, galaxies, and

the whole universe. Astroriomers try to uriderstand how the universe works, They study the evolution of aAars in an

attempt to understand how our own star, the sun, and our solar syslem of planets were crea+ed and what will happen to

them as they age. Aslronomers must Iearn physics, chemistry, computer science, and mathematics. Physics is the study of

the Iaws of nature and how particles interact with one another. Astronomy is a science where aslronomers observe physics

at work throughout the universe! Astronomers use physics fo help them understand what fhey are seeing in all the pretty

pictures that come off the telescopes. Aslronomers have helped physicists discover all kinds of exciting things Iike

relativity, black holes, and nuclear fission. Physics has helped astronomers to understand what makes spiral galaxies have

spiral shapes, how slars form, and even how to delecl ofher planets around other stars! Solar astronomers study our sun.

It has 11-year cycles of solar activity that have a dramatic effect on our daily Iives. Huge solar flares and sunspots result

in charged particles bombarding the Earth and interfering with satellite communication, power grids, and cell phones.

2 0ur galaxy, the Milky Way, is a barred spiral galaxy consisting of 400 billion stars. It is about 100,000 Iight-yearsacross, A light-year is the distance it would take for Iight to travel in one year. Since Iight travels at a speed of about186,000 miles per second, a Iight-year is a huge distance! The universe is made up of an uncountable number of galaxies.Only the nearesl ob3ecls in our solar syslem can be reached by spacecraft in a reasonable Iength of time. Informationabout all the other objects in the universe comes from observations through telescopes or Earth-orbiting satellites. Inthis way, astronomy is different from the other sciences because astronomers can' t have direct confact with the objeclof their study. It's impossible to touch, weigh, or dissect a star! Aslronomers must rely on their observatiori skills, andthey mus+ be able to reason and make sense of what they see. Because distances in space are so huge, aslroriomers mayactually be studying a star that no longer exists. Stars go through Iife cycles just like many Iiving things. Stars are "born"in "nurseries" in nebulae. Huge clouds of dust and gas collapse under gravitational forces, forming prolostars, These youngslars undergo further collapse, forming main sequence slars. Our star, the sun, is still a main sequence star. Stars expandas they grow old. As the core runs out of hydrogen and then helium, the core contracts and the outer Iayers expand, cool,and become Iess bright. This is a red giant or a red super giant (dependirig on the initial mass of the star). It will eventuallycollapse and explode. Its fate is determined by the original mass of the star; it will become a black dwarf, neutron star, orblack hole. Only very large, massive stars become black holes.

3 AAosl astroriomers don't stay awake all night, every night, working at a 'felescope! They work fairly riormal daytimehours most of the year, and only a few times a year they go to a telescope. These trips usually last just a few days. Onmost workdays, aslronomers work on analyzing pictures from the lelescope and writing computer programs to help themwith that work, They plan what kind of piclures they need for their next trip to the lelescope. They work at a computeranalyzing data or making computer models. Most astronomers work at colleges and universities, combining teaching withresearch.

4 It is often said that astronomy is the oldest science, but in many ways it is also the riewest science because year afteryear new discoveries remake our view of the universe. In the past two decades alone, astronomy has experienced a flurryof discoveries never before seeri in its history. Many of these discoveries sound more Iike science fiction than sciencefact: Iight echoes around exploding slars: gamma ray bursts; "greal walls" of galaxies; voids in space; cosmic :3ets:

gravitational lenses: "dark" matter; Einstein rings. Such discoveries reveal a universe richer and more varied than had beensuspected by earlier astronomers.

s The night time sky is a source of beauty and wonder. You can experience this for yourself if you have an uriobstructedview of the dark night sky-just Iook up! We can all marvel at pictures of galaxies, nebulae, planets, and other celestialworiders the heavens coritain, slrelch our minds to comprehend the vast distances involved, and think about the meanirig ofit all. Humans want to know how the universe came into being, what our place in it is, and what other ob:3ects exist within it.Basically, we are curious, and astronomy enriches our lives because we want to "boldly go where no man has gone before."

By Cindy Grigg

Part 2, birections: Ariswer the questions based on the article.

1. What do aslronomers study?

(K> Our solar system% other stars and galaxies% The whole universe('> All of the above

s. What isalight year?

2. What kind of galaxy is our galaxy, the Milky Way?(K> A spiral galaxy% A barred spiral galaxy( > A globular galaxy% An elliptical galaxy

6. Where are stars born?

3. What isa Iight-year?(K> A Iarge unit ot distance0B A large unit ot time% A Iarge galaxy

7. How is astronomy different than olher

sciences?

4. At what stage of its Iife cycle is our sun?(Ki Main sequence(? Black hole% Red giant

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The Hiqhs and Lows of Air PressurePd Date

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Part 1 Directions: Read arid underlirie importaritinformation.

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1 Did you ever walk outside on a hot, humid day and think theair felt heavy? Air has mass, and because of gravity, it ispulled down toward the center of the earth. Usually you don'tnotice the pressure of air on your body because you are used to it. You may hear the weather forecaster talkabout air pressure, but do you know how it affects the weather? What are those H's and L's on the weathermap, and what do they mean?

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2 There are many weather stations in the u.s. Scien'tisls at these stations use many instruments to measurethe weather. They use barometers to measure air pressure in units called millibars. Measurements are taken atmany stations at exactly the same time. This data is used to help scientists tell what kind of weather is coming trithe next hours or days. This is called forecasting.

3 5cientists who study the weather are called meteorologists. They receive data from other weather stationsand put it all on a Iarge map. They write down air pressure measurements at other Iocatioris. They conriect placesthat have the same measurements, kind of Iike a game of dot to dot. These connections form Iines or circles onthe map called isobars. hAeleorologists study the patterns of these isobars to help them forecast the weather.

4 Isobars tell meteorologisls many things. Isobars that are close together show that there is a Iarge pressurediffererice over a small distance. In this area, the wind will be blowing hard. Isobars spaced far apart show areasof calm winds.

s Probably the most important information meteorologists learn from isobars is where high and Iow pressuresystems are forming. If the pressure readings gel higher toward the center of the isobars, there is a high-pressure syslem or a high. It appears as a big H on the weather map. If the pressure readings are lower towardthe center, it is a low-pressure system, whose symbol is a big L.

6 What do lhese high and Iow-pressure syslems tell us? Plenty. In a high-pressure syslem, the air moves inclockwise circle. The air in the middle will sink. It is very hard for clouds to form when the air is sinkirig. Becauseof this, highs usually produce fair weather and sunny skies. The air may be cool and breezy.

7 A Iow-pressure syaAem does the opposite. Air at the middle of a low rises and takes water with it. Lots ofclouds {orm. The air flows in a couriter-clockwise direction. LOWS usually cause rain or snow which is also calledprecipitation.

8 Now you know the highs and Iows of air pressure. The next time you see that big H or big L ori the weathermap, you'll know, even before the weatherman tells you, what kind of weather is coming your way.

By Patti Hutchison

Part 2. Directions: Answer the questions.

1. A scientist who studies the weather is called a

A. MeteorologistB. WeatherologistC. Aslrologisl[). Scienlologisl

2. Air pressure is measured inA. 9egreesB. Feet

C. Inches

D. Millibars

3. How are isobars formed?

4. In a high-pressure system, the rotation of the air is in the directiori.

A. Counterclockwise

B. Clockwise

s. A low-pressure system usually causes what kind of weather?

6. What do isobars that are spaced close together tell us?

7. If a high-pressure system is in place, lhere will be cloudy skies.

8. Why does a high-pressure syslem make it hard for clouds to form?

False

True

9. Which would you rather see on a weather map tri your area, a high or a low? Tell why.

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?Waves and Rays

Part 1 C)irections: Qead and highlight the article.

1 Have you ever played in the ocean? The waves can push you around. They can pull the sand out from underyour feet. As far out as you can see, there are more waves coming at you all +he time.

2 There are other kinds of waves all around you all the time. You can't see most of them, but they can warmyou, burn you, and go right through your body. These are the waves of the electromagnetic spectrum.

3 These waves come from the same kind of electric force that makes your TV work and from the same kindof magnetic force that holds the picture you drew in art class on your kitchen refrigerator with a magnet.When these two forces act togelher, they make electromagnetic radiation. This is a kind of energy that is bothelectric and magnetic, This energy travels in waves,

4 In some ways, these waves and ocean waves are alike. They have tops called cresls. They have bottomscalled troughs. The distance from one cresl to the next is called a wavelength. Wavelengths can also bemeasured from one trough to the next. Another way electromagnetic (EM) waves are Iike ocean waves is thatthey both move energy from one place to another.

s The biggesl difference between ocean waves and EM waves is that ocean waves move across wa+er. Energymoves through the water. EM waves don't need anything to move through. They can move across the emptinessof ouler space. In outer space where there is nothing for the waves to move through, the waves travel at thespeed of Iight. EM waves can also travel through things. They can travel through air inside a room, around theearth, or through food. Some EM waves can even travel inside your body!

6 Let'slearnmoreaboutthesemysteriouswaves.Whenyouturnonaradio,you'reusingpartoftheEMspectrum. Radio waves have the longest wavelengths of any of the waves in the EM spectrum. Radio waves canbe several miles Iong, or they can be about the Iength of a one-foot ruler.

7 When you turn the dial on the radio, you are changing from one radio frequency to another. Frequencymeans how many waves pass a certain point in one secorid. If you could see radio waves, you could stand on thestreet outside your house and count them. Imagine there is a radio tower at the end of your street. The towersends out radio signals. If you could see the radio waves, you could count how many of them pass a point infront of you in one second. A single wave from one creaA fo the next (or one trough to the riext) is called acycle. If jive thousand waves passed the point in front of you in one second, the radio signal would have afrequency of five thousand cycles per second. You'd have to be able to count pretty fast!

8 Another name for cycle per second is hertz. It is abbreviated Hz. Radio waves are used to broadcast radioand TV shows and signals for cellular phones, pagers, and beepers. They carry signals here on Earth andthrough outer space.

9 There are seven different types of EM, The frequency of the waves makes each type different. Frequencyis the number of cycles that pass a given point in one second. The example above (where you counted radiowaves from a tower) had a frequency of five thousand cycles per second. Waves in the EM spectrum that havethe Iowest frequencies have the Ieast amount of energy. Waves wifh the highest frequencies have the moslenergy. The first type we Iearned about is radio waves. The other six types are microwaves, infrared, visibleIight, ultraviolet, X rays, and gamma rays.

10 Microwaves are shorter waves than radio waves - shorler than 11.8 inches. The ones used in microwave

ovens to cook food are about five inches long. How do microwaves cook food? When you put food into amicrowave, the plate stays cool and the food gels hot. Inside food is water. Plates don't have water insidethem. When the microwaves hit the food, the water inside the food begins to vibrate from the energy.Microwaves have a frequency of two billion four hundred fifty million waves per second. The water moleculesvibrate with that same frequency. When molecules vibrate, they move. The movement releases heat inside thefood. The heat cooks the food very quickly.

11 Two billion four hundred fifty million waves per second is a really big number. Scierilisls needed a st?iorlerway to say it. A million cycles is a megaherlz, abbreviated MHz. A thousand megahertz, or 1000 MHz, is thesame as saying one billion cycles per second. The frequency of a microwave can be written as 2450 MHz.Microwaves are also used for communication and TV satellites and for radar. These have shorter waves than

those used for microwave ovens. Communications satellite microwaves can be as short as four-hundredths of an

inch. When a wavelength is that short, the frequency is high - three hundred billion cycles per secorid. This canbe written as 300 GHz, or 300 gigahertz. "Giga" means one billion.

12 Infrared waves are the next ones in the band of EM radiation. If you stand in the sunlight, you can feelwarmth from the sun's infrared radiation. Your TV remote works on infrared waves. When you push a button onyour TV remote, a microchip in the remote slarls a vibration. It produces waves in the infrared rarige.Infrared waves have frequencies of 100 billion fo 100 trillion cycles per second. Here's another prefix to Iearn:"tera" means orie trillion. One terahertz (THz) is one trillion hertz or cycles per second. Since the frequenciesof infrared beams are so high, the wavelengths are short-from four-hundredths of an inch to only four-hundred thousandths of an inch.

13 These infrared beams carry codes. Inside the TV sel, another microchip identifies each code and sends asignal to raise or lower the volume, change channels, turn the set on or off, record a program, or do whateveryou want it to do. Firefighters use infrared cameras to Iook through smoke and find survivors. They are used inbuilding construction to find heating and cooling system Ieaks. They are also used in medicine to diagnosecaricers and injuries, similar to X-rays.

14 Radio, microwaves, and infrared are only part of the waves that make up the EM spectrum. Read Wavesand Rays, Part II fo find out more.

By Cindy Grigg

Part 2 Direcfions: ariswer the quesiioris.

1. All waves need some material to travel through.False

True

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2.. What does frequency mean?A, How many waves or cycles pass a certain point in orie hourB. How many waves or cycles exist at one timeC. How many waves or cycles pass a certain point in one second[). How many waves or cycles pass a certain point in one minute

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'13. Explain how microwaves work to cook food.

Name Pd Date

Electrical Circuits

[)irections Part 1: Read and highlight the article

You have already Iearned about electricity. You know that electricity is astream of eleclrons moving from atom to atom. Electrons have a negativecharge. They move toward atoms with a positive charge. When eleclrorismove, electricity is made.

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Electroris cannot jump across a distance. There must be a path foreleclrons to follow. The path must be a series of atoms that can accept anelectron. We call this path a circuit. People have learned how to build andmanipulate circuits to move electricity. We use circuits to bring electricityinto our homes. We use circuits to move electricity through our computers,telephones, toys, and even our cars.

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3 Every time you flip a Iight switch in your house, you are using a circuit. The Iight bulb glowswhen electrons are flowing through it. The light bulb orily glows when the switch is on. This isbecause the circuit is complete when the switch is on. Wiring in your house forms a path forelectricity to flow. The wires are attached to the light bulb. The wires are also connecfed tothe switch ori the wall. Wheri the switch is turned off, there is a break in the circuit. When the

circuit is broken, electricity cannot flow through the light bulb. When the switch is turned on,the switch forms a bridge that completes the circuit. Electrons can flow through the wires,through the switch, arid through the Iight bulb. The light bulb glows and lights your room.Circuits help people control when arid where electricity flows.

By Brandi Waters

f)irections Part 2: Ariswer the questions

Explain what a switch does in an electrical circuit. How does the circuit changewhen the switch is turned from on to off?

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l1- Electricity is

A. Negatively chargede. A stream of electroris

C. Made when eleclrons move

from atom to atom

f). All of the above

3. People use electrical circuits to

A. Conlrol where electricity flowsand when it is flowingB. Corilrol how much eleclricily ismade

C. Make eleclrons jump topositively charged atoms[). All of the above

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5- What is used to make the il

circuits, or paths that electricitycan flow through, in our homes?A. Light bulbsB. Wires

C, Electrons

[). Switches

'4- When a switch in an electricalcircuit is turned off,

2- Electrons flow on a path called ,

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