2A

1 class session

Physics: The Search for Understanding, pp. 4–12(1/2 class session)

Pocket Lab: Falling, p. 5Physics & Society: Research

Dollars, p. 8Help Wanted: NASA

Researchers, p. 9Physics Lab: Egg Drop Project,

p. 12

Transparency 1: Dice Patterns

Lesson Plans: p. 1ELLL1

Study Guide: pp. 1–6 Transparency 1 Master and

Worksheet: pp. 1–2

Reteaching: pp. 1–2 Laboratory Manual: Lab 1.1

pp. 1–4 Physics Lab and Pocket Lab

Worksheets: pp. 1–3

Critical Thinking: p. 1 Enrichment: p. 1 Tech Prep Applications: Creative

Problem Solving, pp. 1–4

L1

L1

L1

L1

L1

ELLL1

L1

Chapter Review, p. 13(1/2 class session)

SummaryKey TermsReviewing ConceptsApplying ConceptsProblemsGoing Further

Chapter Assessment, pp. 1–4

Spanish Resources, Chapter 1

Cooperative Learning in theScience Classroom

COOP LEARN

ELL

L1TestCheck SoftwareMindJogger Videoquizzes

ELL

L1

Chapter 1 Chapter OrganizerChapter 1 Chapter Organizer

Contents Text Features Teaching Aids Student Masters

The following Glencoe resources provide opportunities forintegrating science and technology.Student Edition: Physics & Society, p. 8; Help Wanted, p. 9Teacher Wraparound Edition: Tech Prep, p. 6; VisualLearning, p. 10Teacher Classroom Resources: Tech Prep Applications,pp. 1–4

TECH PREP

KEY TO TEACHING STRATEGIESThe following designations will help you decide which activities are appropriate for your students.

Level 1 activities should be within the ability range of all students including those with learning difficulties.Level 2 activities should be within the ability range of the average to above-average student.Level 3 activities are designed for the ability range of above-average students.ELL activities should be within the ability range of English Language Learners.Cooperative Learning activities are designed for small group work.These strategies represent student products that can be placed into a best-work portfolio.These strategies are useful in a block scheduling format.

P

COOP LEARN

ELL

L3

L2

L1

Texas Lesson Plans

Reviewing Physics:Mastering the TEKS

2B

Activity and Demonstration Materials

Page 12cushioning materials:

cotton balls, bubble wrap, balloons

drop cloth, plastic (3-m � 3-m)egg, rawgluepan balancepaper towelstapetrash bags

Page 5coin, penny (5)papertape, transparent (10 cm)

1–1, Page 6multimetersolar cell

What is physics?What is physics?

Science and Technology Videodisc Series (STVS)Physics

Mars BallChemistry

Drugs from Snake VenomEarth and Space

Vehicle for the DisabledPhysics for the Computer Age CD-ROM

INTRODUCTION: Physics and the Computer Age

WHAT IS PHYSICS?: Computers and Physics; Hooke’s LawThe Mechanical Universe VideotapeQuad 3: Kinematics and Scientific Methods

The Law of Falling BodiesQuad 4: From Kepler to Einstein

Kepler’s LawsMindJogger Videoquizzes

Chapter 1

The following multimedia resources are available from Glencoe.

1(A), 1(B), 2(A), 2(B), 2(C), 2(D),2(F), 3(A), 3(B), 3(C), 3(D), 3(E)

Physics: The Search for Understanding1. Define physics.2. Relate theory, experiment, and applications to the

role they play in physics research.3. Demonstrate that, while there is no single scientific

method, there are common methods used by all scientists.

UCP.1, UCP.2, UCP.3, UCP.5, A.1,A.2, B.4, D.3, E.1, E.2, F.1, F.6, G.1,G.2, G.3

Objectives State/Local StandardsNational ScienceContent Standards

DemonstrationsPocket LabPhysics Lab

Blast Off!The Mars Pathfinder

hurtled into space to

demonstrate a lower-

cost way to deliver

scientific equipment to

the distant surface of

Mars and send back

data to Earth. What role

does physics play in

missions to Mars?

➥ Look at the text on page 10 for the answer.

What is physics?Chapter OverviewThis chapter will set the tone andattitude for the entire course.Students need to be reminded thatscientists are real people workingon real problems. Physics is not abody of facts, but rather is a processof asking questions and designingexperiments and theories to answerthose questions and explain the answers.

Key Termsphysicsscientific method

2

LS

Learning Styles

Look for the following logo for strategies that emphasize different learning modalities.

Kinesthetic Pocket Lab, p. 5

Visual-Spatial Discrepant Event, p. 4; Quick Demo, p. 5

Interpersonal Cultural Diversity, p. 5; Applying Physics, p. 9; VisualLearning, p. 10; Checking for Understanding, p. 10;Reteaching, p. 11; Physics Lab, p. 12

Intrapersonal Enrichment, p. 6; Meeting Individual Needs, p. 9; Extension, p. 11

Linguistic Demonstration, p. 6; Physics Journal, p. 9

LS

1CHAPTER

Texas TEKS

Pages 2–3: 3(D)

What do you think of when you see the word physics? Doyou recall friends saying how hard it is? Do you think ofchalkboards filled with equations such as E � mc2? Does

the word conjure up images of an atomic bomb’s mushroomcloud? Perhaps you think of scientists in white lab coats. MaybeAlbert Einstein, Marie Curie, or Stephen Hawking comes to mind.

Physics does have a reputation for being difficult. Physics doesuse mathematics as a powerful language. Also, much of physicsrequires that you be as accurate as possible. However, physics alsoinvolves ideas, theories, and principles expressed in ordinarywords. Once you are familiar with physics, you will find that youcan explain the actions of a rocket, a roller coaster, and a baseballcrashing through a window by using the same handful of physicsprinciples.

Yes, many physicists worked together to develop the atomicbomb. Physicists also played a role in developing the computerchips used in PCs and video game systems; the graphite-epoxymaterials used in guitars and golf clubs; the CDs and DVDs onwhich your favorite music, computer games, and movies arerecorded; and the lasers you use to play them. Physics plays a pri-mary role in the development of new technologies for leisure,work, medicine, sports, and nearly any other field you can name.

Albert Einstein, Marie Curie, and Stephen Hawking are exam-ples of remarkable physicists. But there are remarkable physicistseverywhere. Many are women and men who work at universities,two-year colleges, and high schools; industrial and governmentallabs; hospitals; and Wall Street. A physicist could easily be yournext-door neighbor—or you could become one yourself!

What isphysics?

WHAT YOU’LL LEARN• You will learn to ask the

questions “How do weknow?” “Why do we believeit?” and “What’s the evi-dence?” in order to examineand solve problems.

• You will have the satisfactionof understanding and evenpredicting the outcomes ofphysical occurrences allaround you.

WHY IT’S IMPORTANT• An understanding of physics

will help you make informeddecisions as a citizen in anincreasingly complex world.

1CHAPTER

3

PHYSICSTo find out more about physics and missions to Mars, visit theGlencoe Science Web site at science.glencoe.com

Introducing the ChapterUSING THE PHOTO

The blastoff of Mars Pathfinder was agreat day for many U.S. scientistswho had spent much of their pro-fessional lives working on the spaceprogram. Even though the blastoffwent as planned, it was just a firststep in the program to land therover on Mars. The Mars Pathfindermission is only a small part of ourprogram to understand our neigh-boring planets.

3

Hold up a fresh egg and tell stu-dents that it represents anexpensive package of scientificinstruments that were sent up toexplore the surface of Mars. Askthem how they could guaranteethat the package would survivethe landing and could be turnedright-side up. Students should sug-gest rocket engines, parachutes, and(the correct answer) large soft bal-loons to ensure a safe landing.Turning the package right-side upwas accomplished by deflating theballoons in a specific order. L1

DEMOQUICK

Assessment OptionsPORTFOLIO ASSESSMENT

Portfolio Assessment, TWE, p. 8Extension, TWE, p. 11

PERFORMANCE ASSESSMENTPhysics Lab, SE, p. 12Pocket Lab, SE, p. 5

KNOWLEDGE ASSESSMENTKnowledge Assessment, TWE, p. 7Chapter Review, SE, p. 13Demonstration, TWE, p. 7Physics Lab, TWE, p. 12

STUDENT EDITIONPhysics Lab: p. 12Pocket Lab: p. 5

TEACHER EDITIONDemonstration: p. 6Quick Demos: pp. 3, 5

LABORATORY MANUALLab 1.1

PHYSICSBe sure to check the GlencoeScience Web site for links to chapter material: science.glencoe.com

Physics is a branch of knowledge that involves thestudy of the physical world. Physicists investigate objects

as small as subatomic particles and as large as the universe. They study thenatures of matter and energy and how they are related. Physicists and otherscientists look at the world around them with inquisitive eyes. Their observa-tions lead them to ask questions about what they see. What makes the sunshine? How were the planets formed? Of what is matter made? Physicistsmake observations, do experiments, and create models or theories to try toanswer these questions. Finding explanations for the original questions oftenleads to more questions and thus more observations, experiments, and the-ories. The goal of all scientists is to obtain a compelling explanation thatdescribes many different phenomena, makes predictions, and leads to a bet-ter understanding of the universe.

Sometimes the results of the work of physicists are of interest only toother physicists. Other times, their work leads to the development ofdevices such as lasers, communication systems, computers, and newmaterials that change everyone’s life. As an example of how physicsworks, let’s look at the role of the planet Mars, shown in Figure 1–1, inthe development of the scientific method and the exploration of Mars.

The WanderersHave you ever seen the planet Mars? Mars is among the brightest

planets in the night sky. Ancient people were keen observers of celestialobjects in order to define the time of year and find the direction of trav-el on Earth. These observers noticed that five bright “wanderers,” orplanets, generally followed an eastern course through the constellations,yet, unlike the stars, they also moved westward for periods of time. Thedeep-red color of one of those planets caused the Babylonians to asso-ciate it with disaster and the Romans to name it after their god of war,Mars. Early records of the motion of Mars helped develop the early con-cepts of the solar system centuries before the invention of the telescope.

Are the stars and planets like Earth? About 2500 years ago,Greek philosophers tried to determine what the world was made of bymaking observations of everyday occurrences. Some of these scholarsbelieved that all matter on or near Earth was made up of four elements:earth, water, air, and fire. Each element was thought to have a naturalplace based on its heaviness. The highest place belonged to fire, thenext to air, then water, and, at the bottom, earth. Motion was thoughtto occur because an element traveled in a straight line toward its ownnatural place.

OBJ ECTIVES• Define physics.

• Relate theory, experiment,and applications to the rolethey play in physicsresearch.

• Demonstrate that, whilethere is no single scientificmethod, there are commonmethods used by all scientists.

4 What is physics?

FIGURE 1–1 NASA scientistsused 102 images taken by theViking Orbiter to form this mosaicof Mars.

Physics: The Search for Understanding

PREPAREContent RefresherAsk students why we would want tosend a mission to Mars and what isthe practical value of such a mis-sion. Remind students that scienceis a process of learning about theuniverse. The really important ques-tions are the ones for which we donot yet know the answers. The mis-sions to Mars may yield importanttechnologies that will be developedand marketed in the near future.

BridgingMen and women have looked at thenight skies for centuries. Only inthe past three centuries have webeen able to see clearly the moun-tains and craters on the surface ofthe moon and Mars. Only withinthe last three decades have we beenable to take close-up photos andsample the surface materials.

1 FOCUSDiscrepant Event

Visual-Spatial Hold up apicture of the Martian surface andpoint out a particular rock. Nowhold up a common Earth rock. Askstudents how the materials are thesame and how they are different.Both are solid and have similar chemi-cal elements. An overall red tint mayindicate that the Martian rock has ahigher iron content. Both might showsome signs of erosion due to water. Askstudents why they think scientistsare really interested in accuratelyestimating the age of the Martianrocks. Answers may vary. L1

LS

4

Program Resources

Study Guide, pp. 1–6 Transparency 1 and Master Laboratory Manual, pp. 1–4 Reteaching, pp. 1–2

Critical Thinking, p. 1 Enrichment, p. 1 Physics Lab and Pocket Lab Worksheets,

p. 1

Tech Prep Applications, pp. 1–4 L1

L1

L1

L1

L1

L1

ELLL1

L1

CD-ROMPhysics for the Computer AgeINTRODUCTION: Physics and the Computer Age

Texas TEKS

Pages 4–5: 3(A), 3(C), 3(D), 3(E)

Ancient people observed that the sun, moon, stars, and planets suchas Mars didn’t behave this way. As far as anyone could see, these celestialbodies were perfect spheres and moved in circles about Earth forever.They certainly didn’t obey the same laws of motion as objects on Earth,and so it seemed that they couldn’t be made of the four elements; rather,they were formed of a fifth element, quintessence.

The writings of these early Greeks, lost to Europe for hundreds ofyears, were studied and translated by Arabic scholars. In the twelfth cen-tury, the writings made their way to Europe and were accepted as truththat did not have to be questioned or tested. One of the first Europeanscientists who claimed publicly that the ancient books were no substi-tute for observations and experiments was Galileo Galilei (1564-1642).

Galileo and Scientific MethodsIn 1609, Galileo built a telescope shown in Figure 1–2, powerful

enough to explore the skies. He found that the moon wasn’t a perfectsphere, but had mountains, whose heights he could estimate from theshadows they cast. He discovered four moons circling the planet Jupiter,that the Milky Way was made up of many more stars than anyone hadthought, and that Venus had phases. As a result, Galileo argued that Earthand the other planets actually circled the sun.

As Galileo studied astronomy and the motion of objects on Earth, hedeveloped a systematic method of observing, experimenting, and ana-lyzing that is now referred to as a scientific method. Rather than writ-ing his results in Latin, the language of scholars, he wrote them in hisnative Italian so that any educated person could read and understandthem. For these reasons, Galileo is considered to be the father of modernexperimental science.

Physics: The Search for Understanding 5

FIGURE 1–2 The telescope (a)and the lens (b) with whichGalileo first observed the moonsof Jupiter are on display at theMuseo di Storia della Scienza inFlorence, Italy.

a b

Pocket LabFalling

The Greek philosophers arguedthat heavy objects fall fasterthan light objects. Galileo stated that light and heavyobjects fall at the same rate.What do you think? Drop fourpennies taped together and asingle penny from the sameheight at the same time. Tear asheet of paper in half. Crumpleone piece into a ball. Repeatyour experiment with the paperball and the half sheet of paper. What did you observeeach time? Analyze and Conclude Whowas correct, the Greeks orGalileo?

2 TEACH

5

Visual-Spatial Galileowas able to estimate the heightsof the mountains on the moonby estimating the lengths of theshadows. Ask a student to cometo the front of the room to holda shoe box and a 30-cm ruler sothat they are on your white pro-jection screen and pointing out-ward. Now use a flashlight tosimultaneously make shadows ofthe two objects on the screen.Have students note that the tallerobject makes a longer shadow,and each shadow length is inproportion to the height of theobject.

flashlight here to represent the sun

TOP VIEW

L1

LS

DEMOQUICK

FallingPurpose To discover how the motionof a falling object depends on sur-face area and mass

Materials Sheet of paper, 5 pennies,10-cm of transparent tape

Outcome The ball of paper hits firstbecause it has less air resistancethan the half sheet. The four pennieshit at the same time as the singlepenny.

Analyze and Conclude Aristotle waswrong. If Aristotle were correct, thefour pennies would have fallen fasterthan the single penny and reachedthe ground first. LS

Cultural DiversityCultural Diversity

Interpersonal Ask students to closetheir eyes and to see in their minds a physicistat work. Ask them to keep their eyes closeduntil they can see some details. Tell studentsthat they will be asked to share some of thedetails with the rest of the class. After aminute or two, ask them to open their eyesand share what they imagined. Write theirresponses on the board. Typical responses

include man with thick glasses, man with whitelab coat, man with white unkempt hair. Moststudents will see a caricature of Einstein.Assure them that scientists come in bothsexes, in various colors, and speak many lan-guages. The only common factors are deepcuriosity and a willingness to work on diffi-cult problems. ELLL1

LS

Galileo’s methods are not the only scientific method. All scientists muststudy problems in an organized way. They combine systematic experi-mentation with careful measurements and analyses of results. From theseanalyses, conclusions are drawn. These conclusions are then subjected toadditional tests to find out whether they are valid. Since Galileo’s time, sci-entists all over the world have used these techniques and methods to gaina better understanding of the universe. Knowledge, skill, luck, imagina-tion, trial and error, educated guesses, and great patience all play a part.

Mars in Recent TimesAs telescopes improved, Mars became much more interesting to

astronomers and to people in general because they thought it lookedmuch like Earth. Astronomers found what appeared to be ice caps thatadvance and recede, color changes they attributed to vegetation cyclessimilar to Earth’s seasons, and dark areas believed to be seas. To someearly observers, strange markings on the surface of Mars, shown in Figure 1–3, were mistakenly interpreted as being channels or canalspossibly made by intelligent beings. This interpretation became soprevalent that a 1938 radio drama, depicting a Martian invasion ofEarth, caused widespread panic in the United States.

When rockets capable of reaching our neighboring planet were devel-oped in the 1960s, both the United States and the former Soviet Unionlaunched a series of probes designed to orbit Mars, take photographs,and land on the planet to return data. A timetable of these probes isshown in Table 1–1.

The first of the recent probes, Mars Pathfinder, surrounded by protec-tive airbags, bounded down on Mars on July 4, 1997. The entire missioncost less than the production of one Hollywood movie. A 10-kg robotrover, named Sojourner, was released to explore nearby rocks. Millions ofpeople used the Internet to retrieve photos directly from the NASA web-sites into their home computers. The new era of Martian explorationhad begun.

6 What is physics?

FIGURE 1–3 During the 17th,18th, and 19th centuries, it waswidely believed that Mars wasinhabited. Dark linear featureswere interpreted as canals.

UncoveringMisconceptionsMost students believe that all of theanswers to scientific questions canbe found in the back of a book. Ask students why we sent the mis-sion to Mars. To try to answer funda-mental questions regarding the age andsurface features of Mars, and to findevidence that might give clues aboutthe water that we believe was once onthe surface.

Point out that science is not abody of facts, but rather a processof asking questions and designingtheories and experiments to try toanswer those questions.

EnrichmentIntrapersonal Ask your more

capable students to use the mediacenter to find the times of traveland also the average speeds of thespacecraft that took men to themoon. Then have them find thesame information for the latestMars mission. Have them find outwhy the speed of the Mars probewas so much faster than that of the moon missions. The distancebetween Earth and Mars is over 2 � 105 greater than the distancebetween Earth and the moon.Greater speed is needed to cover thedistance in a convenient period oftime. A manned spacecraft cannotexperience as much acceleration as anunmanned craft. Equipment can sur-vive much higher accelerations thanpeople can. L2

LS

6

PURPOSETo discover how the current from a solar celldepends on the area, the sunlight, and theangle of the light

MATERIALSSolar cell, multimeter, sunny day

PROCEDURE 1. Have students follow your instructions

to put the multimeter in the setting tomeasure the current.

2. Take the equipment outside to measure thecurrent when the solar cell is facing thesun directly. Record the current.

3. Keep the solar cell facing the sun and coverabout half of the surface with someone’shand. Record the current.

4. Uncover the solar cell, and turn the panelso that the angle to the sun is about 45°.Record the current.

GLOBAL POSITIONINGSYSTEMSGlobal positioning systemsallow sailors, hikers, and driversto determine their location onthe surface of Earth to within afew meters. Ask each class if any-one has a GPS device. If so, askthe student to demonstrate it tohis or her classmates and see ifyou can use it with your otherclasses. Be sure to have appropri-ate maps to take full advantageof the device. ELLL1

TECHPREP

DEMONSTRATION 1-1

Missions to Mars Accomplishments

1964 U.S. Mariner 4 First photos from 16 898 to 9846 km above surface.USSR Zond 2 Failed to send back data.

1969 U.S. Mariner 6 Examination of Martian equatorial region from an altitude of 3430 km.U.S. Mariner 7 Examination of the Martian southern hemisphere and south polar

ice cap from an altitude of 3430 km.1971 USSR Mars 2 Martian orbit.

USSR Mars 3 Lander on Martian surface.U.S. Mariner 9 Photographs of entire Martian globe from orbit.

1973 USSR Mars 5 Martian orbit.1975 U.S. Viking 1 Panoramic views and close-up photos from the Martian surface.

U.S. Viking 2 Automated experiments on the Martian surface.1988 USSR Phobos 2 Martian orbit.1993 U.S. Mars Observer Lost during mission.1996 U.S. Global Surveyor Record of surface features, atmospheric data, and magnetic

properties from Martian orbit.U.S. Mars Pathfinder Surface landing and release of a mobile vehicle to explore Ares Vallis.

1998 U.S. Mars Surveyor Orbiter Lost during mission.1999 U.S. Mars Surveyor Lander Lost during mission.

Goals

2001 U.S. Mars Odyssey To map elemental composition, mineralogy, and morphology of theMartian surface, and to measure the radiation environment.

2002 U.S. orbiters and landers To replace communications relay satellites with new orbiters;and to continue analyses of Martian atmosphere and surface with beyond orbiters and landers.

U.S. sample-and-return To return Martian rock and soil samples to Earth.spacecraft

Why study Mars? Mars had seemed in many ways to be similar toEarth. But the probes have confirmed that its climate is very different.Mars is an ideal laboratory for scientists interested in geology andatmospheric physics.

From the study of Mars, scientists may learn more about the types ofconditions that could lead to dramatic climatic or atmospheric changeson our own planet, and about the formation and evolution of the entiresolar system. These studies may help us understand why Mars grew coldwith almost no atmosphere early in its history while Venus and Earthdid not.

The search for water is central to future explorations. Mars’s northernpolar cap contains water in the form of ice, a vital ingredient for futurehuman exploration. Furthermore, there is evidence that gigantic floodshelped shape the surface of Mars billions of years ago. What happenedto that water? Is it combined with rocks, is it frozen underground, or hasit escaped into space?

Physics: The Search for Understanding 7

TABLE 1–1

F.Y.I.The 1997 Mars roverSojourner was named after Sojourner Truth, anineteenth-century African American womanwho traveled the UnitedStates preaching againstslavery. Sojourner means “traveler.”

7

KNOWLEDGE Ask studentswhat keeps the Mars rover andother objects from floating away.Each planet has its own gravita-tional pull. Then ask students whatfactors determine the value oflocal gravity on each planet. Thelocal gravity depends on the massand the radius of the planet. L1

Assessment

THE ¤MECHANICAL ¤

¤UNIVERSEHIGH SCHOOL ADAPTATION

VideotapeQuad 3: Kinematics andScientific MethodsThe Law of Falling Bodies

Quad 4: From Kepler toEinsteinKepler’s Laws

VideodiscSTVS: PhysicsDisc 1, Side 2Mars Ball (Ch. 3)

!7JÅ"

CD-ROMPhysics for the Computer AgeWHAT IS PHYSICS?: Computersand Physics; Hooke’s Law

RESULTSMaximum current will be recorded when thegreatest amount of surface area of the solarcell is facing directly toward the sunlight.

KNOWLEDGE Write a statement thatdescribes how the current depends on the sur-face area and the angle between the sun andthe panel. LSELLL1

Texas TEKS

Pages 6–7: 3(C), 3(E)

Assessment

8 What is physics?

Research DollarsSome scientific discoveries are made bychance, but most are the result of years ofcarefully planned research. Most scientists arepaid to conduct research—exploring ideas,creating hypotheses, performing experiments,and publishing findings. Professors at univer-sities and their students spend a significantamount of time in the laboratory. Other sci-entists work for government-funded labora-tories or for private companies and spendvirtually all of their time doing research.

Who will pay?Where does the money to pay for thisresearch come from? In the case of universityprofessors, much of the support comes fromgrants supplied by the government, privatefoundations, or private companies. Govern-ment-funded laboratories receive moneyfrom the federal budget. Private companiesfund their own projects, often using profitsearned by inventions developed in previous,successful research. Sometimes, private com-panies are hired by government agencies toparticipate in large projects.

What will be funded?Decisions about funding with limitedresearch dollars are often based on how wella scientist can express to others the impor-tance of the research project. Written andoral communication skills are vital to everyscientist. The scientist must have a goodunderstanding of how the proposed projectwill carry forward previous research.

Every scientist must spend time studyingand evaluating the work of other scientists.He or she must also be able to clearly com-municate why the work is needed and who

could benefit from its results. Becoming a scientist requires not only an education in achosen field of study, but also the ability tothink critically and communicate effectively.

Who will benefit?Not everyone agrees about the kinds ofresearch that should be funded, or even howmuch money should be spent on scientificresearch in general. This is especially truewhen research funds come from the govern-ment. Taxpayers often disagree with govern-ment spending decisions. Some peoplebelieve that their money would be betterspent on solving more immediate humanproblems, such as feeding the hungry, shelter-ing the homeless, and curing disease. Othersargue that the benefits humans derive fromexploratory research are well worth their cost.

Investigating the Issue1. Communicating Ideas Read several

articles from publications such as ScienceNews or Scientific American aboutadvances in scientific research. Write abrief essay about the research areas thatyou feel are most interesting or important.

2. Debating the Issue Should the U.S. government support research in outerspace, or should the money go towardresearch in areas with more humanitarianapplications?

PHYSICSTo find out more about scientific research, visit theGlencoe Science Web site atscience.glencoe.com

BackgroundDetailed information about aplanned research project is oftencontained in a written documentcalled a research proposal explain-ing why the research is important,the project’s hypothesis and objec-tives, experimental methods to beused, and a budget and schedule.Once the research project is com-pleted, a report that describes theresults and conclusions of the workis written. This report is submittedto the agency that supported theresearch, and also may be pub-lished in a scientific journal or pre-sented orally at a scientific confer-ence, or both.

Teaching Strategies• Ask students to give examples of

how NASA has accomplished itsvision to “boldly expand frontiersin air and space to inspire andserve America and to benefit thequality of life on Earth.”

• Ask students to choose an aspectof a NASA mission and considerhow they would write theresearch proposal.

• Ask students to research NASA’sefforts to control research costs.

Investigating the Issue1. Student answers will vary,

depending on their interests.Some may argue that appliedresearch, such as medicalsearches for disease cures, aremore important and deservemore funding. Others may arguethat basic research areas, such asparticle physics or cosmology,are also important because theoutcome of these studies cannotbe predicted and could produceextremely valuable results.

2. Students who prefer more appli-cation-oriented research mayargue that funds are limited andeverything possible must bedone to improve the quality of

L1

PL1

L1

human life. Students who agree with spacescience funding may argue that humans haveno way of predicting what will result fromexploration, and that the benefits that spaceexploration has provided so far are wellworth the cost.

8

PHYSICSBe sure to check the Glencoe ScienceWeb site for links to chapter material: science.glencoe.com

If Mars were a warmer, wetter world early in its history, what hap-pened to cause such climatic devastation and render it lifeless, barren,and frigid? Have there ever been life forms on Mars? Living systems onMars today would have to be able to survive without oxygen, store waterfor long periods of time, and live underground or have protection fromsolar radiation and large temperature fluctuations. In 1976, the Vikinglanders found no evidence of life. But in 1996, scientists claimed to haveevidence of primitive life forms in meteorites found in Antarctica thatthey strongly believed had Martian origins.

Who will study Mars? The Mars exploration team is made up ofmany women and men. Some represent the sciences, including physics,chemistry, geology, and astronomy. Others are electrical, mechanical,aeronautic, or computer engineers. Still others are technicians, graphicdesigners, managers, and administrators. All share some common char-acteristics. They are curious, creative, and interested in mysteries and insolving problems. They love their work, but they also have many outsideinterests such as music, drama, sports, and mountain climbing. Whenthey were younger they took science and mathematics courses, but theywere also involved in many activities in and out of school.

The members of the Mars exploration team had to join their individ-ual experiences and learn to work together, as shown in Figure 1–4.They report that it can be harder to work with a team than on their own,but that the team can do more, and so the rewards can be greater. Theyalso have found that it’s more fun when they can share ideas and expe-riences with others.

Physics: The Search for Understanding 9

HELP WANTEDNASA RESEARCHERSSeeking researchers forNASA’s Jet Propulsion Labo-ratory (JPL) and other spacecenters in the United States.Positions are available in engi-neering, aeronautics, robotics,computer systems, fluid andflight mechanics, chemistry,materials and structures, andtelecommunications. Also hiring researchers in lunar and planetary studies, meteo-rology, radiation, and relatedareas. Some projects requirespecialists in physiology, psy-chology, botany, and biology.Contact: JPL4800 Oak Grove DriveStaffing OfficeMail Stop 249-104Pasadena, CA 91109-8099

FIGURE 1–4 Jet Propulsion Laboratory scientists prepare theMars Pathfinder for placement atop a Delta II launch vehicle.

F.Y.I.Mae Jemison relied onexperience as engineer,physician, educator, andfirst African Americanwoman astronaut to foundThe Jemison Institute forAdvancing Technology inDeveloping Countries.

9

TEAMWORK

Interpersonal The successof the Mars mission was a resultof teamwork. Divide your classinto teams with four or five stu-dents on each team. Ask studentsto choose roles of electrical engi-neer, communications expert,geologist, public relations man-ager, and photographer for theirgroup. Give students time todiscuss how they must worktogether for the good of the mis-sion. Ask students to use theInternet to find out the impor-tant work of these specialists.

COOP LEARNELL

L1

LS

Applying Physics

Linguistic A researchphysicist was recently on an air-plane when a young boy askedhim what job he did. The manidentified himself as a scientistworking on a difficult problem.The child asked how long hehad been working on the prob-lem. When the man told him six years, the boy exclaimed thathe must not be very smart. Aftera moment, the boy suggestedthat he just look in the back ofthe book.

Ask students to write downtheir thoughts on how the ques-tions about Mars might beanswered. L1

LS

Physics JournalPhysics Journal

Gifted Ask your technically astute studentsto find several good sites on the Internet sothat other students will be able to find outthe latest information from the Mars mis-sions. Have them compile their sites to dis-tribute to the entire class. LSL3

MeetingIndividual Needs

MeetingIndividual Needs

Texas TEKS

Pages 8–9: 3(C), 3(D), 3(E)

There is room on the team for you. Thanks to the Internet, you cansend E-mail to the Mars exploration team and ask questions. You alsocan follow the probes’ progress: you can see the photos before theyappear in the newspapers and obtain more complete coverage of theresults than that which is provided in the ten seconds that fits into localtelevision news. You can choose your course of study so that you canbecome part of future space exploration.

Is physics important? Most physicists are not involved directly inthe Mars explorations. Most of the people directly involved in the Marsmissions are not physicists, nor did they major in physics in college.

But the Mars missions are based on physics, starting with the designof the rocket engines, the gyroscopic directional controls, and the preci-sion clocks that are needed to indicate where the spacecraft is and howfast it is moving. The solar panels and nuclear electrical sources thatkeep the probes in contact with Earth during flight are based on physics.Physics is also involved in the design of the cameras, computers, radiotransmitters, and receivers that send the photos back to us.

Science and technology constantly interact. Sometimes, scientificresults produce new equipment for use outside the scientific community.The efficient design of the mechanical arms that allow the rovers to sam-ple the surface of Mars may be used to make artificial limbs for peoplewith disabilities. Similarly, new equipment produces new scientificresults. Advances in computer technology allow faster, lighter computersto be placed on board the spacecraft. As shown in Figure 1–5, the appli-cations of such discoveries affect all our lives.

All participants in the Mars missions use the problem-solving skillsthat they learned in physics and other science courses every day. Theycan’t find answers in the back of a book or by asking a friend! They havelearned the skills that enable them to go forward from a predicament toa decision by choosing relevant information, making logical decisions,and applying old applications to new situations and new applicationsto old situations. Above all, they have learned how to work as a team:dividing the work but making sure that everyone understands, exploringall possibilities but agreeing on one method, and checking to make surethat the problem really was solved. Finally, they have learned how tomake presentations, orally or in writing, that communicate what theyhave learned to their coworkers, their friends, and the general public.

The goal of this course is not to make you a physicist. It is to show youthe way that physicists view the world and to give you an understandingof the physical world around you. It may be that you will become inter-ested in a rewarding career in science or technology. Whatever your cho-sen career, you will be able to make better-informed decisions in anincreasingly complex age. You will learn to ask the questions “How dowe know?”, “Why do we believe it?”, and “What’s the evidence for that?”when you are presented with new information or new problems.

10 What is physics?

Blast Off!➥ Answers question from

page 2.

Visual LearningAsk students to considerthe devices pictured onpage 11. These are technol-ogy applications that

resulted from scientific research. Thelaser was designed without a specificpractical application in mind.Microwaves were originally studiedfor radar. Computers have changedthe way in which we live and work.More energy-efficient transportationand building construction may allowus to conserve our natural resources,create less pollution, and, therefore,live in a cleaner environment.Advances in microscale technologymay lead to breakthroughs in thediagnoses and treatment of disease.Have students separate into groupsto discuss the differences betweenscience and technology.

3 ASSESSChecking forUnderstanding

Interpersonal Ask studentsto make a list of contributions ofscience and to rank their signifi-cance on a scale of 1 to 10. Ask stu-dents to use a 1 for insignificantand a 10 for very significant. Afterstudents write down their numbers,ask them to defend their answerwith their neighbors. Choose stu-dents who are at the extremes todefend their answers to the rest ofthe class. ELLL1

LS

LSL1

10

Connections To Mathematics

SIR ISAAC NEWTONAlthough many physicists excel in mathemat-ics, Isaac Newton was one of the greatest. Hiswork Principia laid the foundations of mathe-matical physics. His contributions include thelaws of motion and gravitational attraction,the discovery of the nature of white light, andthe development of differential and integralcalculus. Ask students to investigate Newton’scontributions to mathematics. As a result of his

work, Newton was able to work out the details ofEarth’s motion, accurately estimate the mass ofthe sun and Earth, prove that the tides were theresult of the moon’s gravitational attraction,explain the orbits of comets, and lay the founda-tion for the treatment of wave motion.

TECHPREP

VideodiscSTVS: Earth & SpaceDisc 3, Side 1Vehicle for the Disabled (Ch. 13)

!8JÇ"STVS: ChemistryDisc 2, Side 1Drugs from Snake Venom (Ch. 16)

!8hÖ"

Physics: The Search for Understanding

FIGURE 1–5

11

Originally thought to serve no usefulpurpose, lasers are now used in indus-try and construction, data storage andretrieval, medicine, telecommunica-tions, navigation, and defense.

We are surrounded in our daily lives byphysics success stories. Examine a fewhighlights below.

The nano-technologythat built thisguitar willallow scien-tists to studyprocessesand performfunctions ona submicro-scopic level.

Razor blades are coatedwith thin film materialsusing plasma physicstechniques. The bladehandles are attached bylaser welding. Computer-ized vision systems qual-ity check each batch.

Billions of dollarsare saved by con-sumers as automo-biles are built withlighter compositematerials and poly-mers, with micro-computers to con-trol fuel injectionsystems, and withmore efficient fuelcells and batteries.

Built during the1940s, the ENIAC comput-er weighed 30tons. Researchon thin films,magnetic mate-rials, and semi-conductors hasled to small,affordable personal computers.

Energy efficient houses are a result ofphysics research on heat transfer, thinfilms, plasma sources, vacuum tech-nology, optics, and new materials.

Wartimeresearch intoradar andminiature elec-tronics led tothe develop-ment ofmicrowaveovens.

6

7

3

2

1

5

4Reteaching

Interpersonal Hold up apen-style laser and shine it on thewall. Tell students that this devicewas originally called a solution insearch of a problem. Divide theclass into rows, and ask each rowfor a different application of a laser.Continue the competition witheach row until they run out ofexamples.

ExtensionIntrapersonal Have students

research the major professionalsocieties in physics and their mainfunctions. The major professionalorganization in physics is the AmericanPhysical Society (APS), which is dedi-cated to the advancement of the knowl-edge of physics and to spreading thisknowledge through meetings and publi-cations for its members and the widerpublic.

4 CLOSEAsk students how science is differ-ent from merely cataloging facts.Ask what the value of science is.Science is an ongoing search to explainhow the universe works; its value is in giving us predictive power, as well as offering new devices to give us aricher life.

PL1

LS

COOP LEARNELLL1

LS

11

VideotapeMindJogger VideoquizzesChapter 1: What is physics?Have students work in groups asthey play the videoquiz game toreview key chapter concepts

Program Resources

Chapter Assessment, pp. 1–4 Computer Test Bank, Chapter 1 MindJogger Videoquizzes, Chapter 1

Alternate Assessment in the ScienceClassroom

Performance Assessment in the ScienceClassroom L1

ELL

L1

L1

L1

PHYSICSBe sure to check the Glencoe ScienceWeb site for links to chapter material: science.glencoe.com

Texas TEKS

Pages 10–11: 3(C), 3(D), 3(E)

Process Skills Observing, formulating models,measuring, predicting, inferring,communicating

UncoveringMisconceptionsStudents often believe that physicsis done by individuals working inisolation, not teams.

Safety Precautions Be sure students handle sharpobjects with care. Clean up any broken eggs immediately to avoidaccidents due to slipping.

Teaching Suggestions• Have students organize their

materials and assign tasks to each member of their groupbefore beginning the design oftheir container.

• Emphasize the need for discus-sion and cooperation amongteam members and the trial-and-error nature of most any scienceproject.

• You may wish to add time restric-tions for the design, construction,and test stages of the experiment.

Data and ObservationsMany of the groups will try wrapping the egg mummy-style.

Analyze and Conclude 1. Students’ responses will vary.

Many students will find theopening and closing restrictionthe most troublesome.

2. Some students will have diffi-culty isolating parts of the designand determining which waseffective and which was not.

COOP LEARN

LS

Apply1. Students will most likely pair two containers,

an egg in each, rather than redesigning theircontainer so it can accommodate two eggs.

KNOWLEDGE To further assess students’understanding of designing protective containers,ask the following question.

1. Why was the mass of the container in thedenominator of the scoring formula? Anypackaging on space flights needs to have as smalla mass as possible to conserve fuel. Placing themass in the denominator of the formula ensuresthat containers with less mass earn higher scores.

12

12 What is physics?

ProblemInstruments destined to explore Mars or the moon must be packaged so that they are not damaged upon takeoff or landing.You and your partners will create a model for that package. You will design a containerfor an egg that will keep the egg from breaking when dropped from a height ofapproximately 5 meters.

Possible MaterialsCushioning materials such as cotton balls,

bubble wrap, balloons, and so ontape, glueraw egg pan balance3-m � 3-m square plastic drop clothpaper towels and trash bags

Procedure1. Work with your group to think of several

container designs that might protect anegg. Follow the restrictions below.

• The design must allow easy opening andclosing for egg inspection.

• Before the container is dropped, it mustfit into a 25-cm � 25-cm � 25-cm cube.

• No liquids are allowed.

• The egg must be raw, its shell uncoated.

• The egg must survive a drop fromapproximately 5 meters.

• Designs with lower mass receive higher scores.

2. Decide which aspects of each idea shouldbe incorporated into your final design.

3. Plan ahead. Set a timetable for experi-mentation, construction, testing, and redesigning if needed.

4. Make a list of materials you would like touse for your package.

5. Produce a detailed diagram or illustrationof your container. Indicate which featuresyou expect will contribute directly to thesafety of the egg.

6. Plan for a test drop of a few centimeters. Ifyour egg breaks, revise your design. If youare satisfied with your design, continue.

7. Record the mass of your container(including egg).

8. Complete the actual egg drop. Inspectyour egg. Give your container 10 points ifthe egg is unbroken, 5 points if the shell iscracked, �

12� point if the egg is broken. Find

your score using the information below.earned

Score ��mass o2f0c0o0ntainer�� egg

points

9. Dispose of the egg and materials with eggon them as instructed by your teacher.Clean and put away materials that can be reused.

Analyze and Conclude1. Compare and Contrast Which restriction

did your team feel was the most limiting?

2. Analyzing the Results What was themost effective part of your design? Whatwas the weakest part?

Apply1. How would your container need to be

redesigned so that it could safely carrytwo raw eggs?

Egg Drop Project

ContainerGroup Design Mass Score

Data and Observations

12

AssessmentTexas TEKS

Pages 12–13: 1(A), 1(B), 2(A),2(B), 2(C), 2(D), 2(F), 3(A), 3(B),3(C), 3(D), 3(E)

13

1 CHAPTER REVIEW

Chapter 1 Review 13

• Physics is the study of matter and energy and their relationships.• Physics is basic to all other sciences.• A knowledge of physics makes us, as citizens, better able to make

decisions about questions related to science and technology.• Much scientific work is done in groups in which people collaborate with

one another.

Key Terms

• physics

• scientificmethod

Summary

CHAPTER 1 REVIEW

Reviewing Concepts1. Define physics in your own words.2. Why is mathematics important to science?3. Assume for a moment that the theory of matter

held by some of the ancient Greeks is correct.How does this theory explain the motion of the four elements?

Applying Concepts4. Give some examples of applications that resulted

from work done by physicists.5. Give some examples of applications that have

resulted from work done by physicists on theexploration of space.

6. Research the aspects of nature investigated byeach of the following kinds of scientists: astrophysicists, astronomers, biophysicists, exobiologists, and geophysicists.

7. Some of the branches of physics that you will studyin this course investigate motion, the properties ofmaterials, sound, light, electricity and magnetism,properties of atoms, and nuclear reactions. Give atleast one example of an application of each branch.

8. What reason might the Greeks have had not toquestion the evidence that heavier objects fallfaster than lighter objects? Hint: Did you everquestion which falls faster?

9. Is the scientific method a clearly defined set ofsteps and procedures? Support your answer.

10. Why will the work of a physicist never be finished?

Critical Thinking Problems11. It has been said that a fool can ask more questions

than a wise man can answer. In science, it is fre-quently the case that a wise man is needed to askthe right question rather than to answer it. Explain.

Going FurtherClass Discussion In 1996, scientists reported that mete-orites found in Antarctica were actually from Mars, prob-ably ejected from that planet by the impact of a meteoror comet millions of years ago. These meteorites wereespecially interesting because they contain structuresthat were interpreted as evidence of simple life-forms.

As a group, brainstorm ways to develop answersto the three questions “How do we know?”, “Why dowe believe it?”, and “What’s the evidence for that?”regarding the composition of these meteorites.

Project Research and describe the history of physics. Be sure to include the contributions of scientists inphysics and the impact of their contributions on science, society, and the environment. Evaluate theimpact of the research and contributions of these scientists on scientific thought, society, and the envi-ronment. How have these contributions impactedyour own life?

PHYSICSTo review content, do the interactive quizzes on theGlencoe Science Web site atscience.glencoe.com

Review the Summary statementsand Key Terms with your students.

Reviewing Concepts1. Physics is the study of the basic

physical laws that can beapplied to all the sciences.

2. Mathematics is the interna-tional, clear language of sciencethat can be used to communi-cate what has been learned tocoworkers, fellow scientists,and the general public.

3. Aristotle’s elements, earth, air,fire, and water, each had a nat-ural place based on its heavi-ness. Motion occurred becausean element traveled in a straightline toward its natural place.

Applying Concepts4. Student answers may include the

atomic bomb, electricity, CDs,computers, and space travel.

5. Student answers may includecomputers, components, newmaterials, and robotics.

6. Astrophysicist: studies thebranch of astronomy that dealswith the physical properties ofcelestial objects; astronomer:studies the material universebeyond Earth’s atmosphere;biophysicist: studies the biolog-ical phenomena using the prin-ciples and techniques of physics;exobiologist: studies the possi-bility of the existence of livingorganisms elsewhere in the uni-verse than on Earth; geophysi-cist: studies the physics of Earth.

7. Student answers may includethe following: motion—improved design of equipmentsuch as skis; properties of materials—heat pumps; light—mixing spotlights to make a different color; electricity—electric motors; magnetism—television; nuclear physics—CAT scans; sound—ultrasonics.

8. Air resistance affects many lightobjects. Without controlledexperiments, their everydayobservations told them thatheavier objects did fall faster.

9. There is no definite order of specific steps.However, whatever approach is used, italways includes close observation, con-trolled experimentation, summarizing,checking, rechecking, rechecking . . .

10. The more questions physicists answer, themore they will have.

Critical ThinkingProblems11. Often, the training, experience, and

imagination necessary to know just whatquestion to ask have provided the insightnecessary to find the answer.

Going FurtherClass Discussion Group answers will vary.Encourage students to discuss all three questionsand to develop their own viewpoints.

Project Student answers will vary. Answers caninclude ancient Greeks, Newton, Maxwell, andother physicists. The contributions of physicistshave impacted how people live their lives, especially through technology.

13