teacher’s guide for: lasers and...

Contents:

Quick Reference Sheets:• Intro(none) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .• Demos:Mirrors and Rainbows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page2• Experiment:Lasers and Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page3• EquipmentList:Lasers and Mirrors . . . . . . . . . . . . . . . . . . . . . . . . .page4• Story,Part1:The Ghost in the Gold Mine . . . . . . . . . . . . . . . . . . . . .page5• Story,Ending . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page6

Video Transcript:• Story,Part1:The Ghost in the Gold Mine . . . . . . . . . . . . . . . . . . . . .page7• Demos:Mirrors and Rainbows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page9• Experiment:Lasers and Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . .page12• StoryEnding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .page13

Teacher’s Guide for:

Lasers and MirrorsNote: All activities in this document should be performed with adult supervision. Likewise, common sense and care are essential to the conduct of any and all activities, whether described in this document or otherwise. Parents or guardians should supervise children. Rock-it Science assumes no responsibility for any injuries or damages arising from any activities.

Note: All activities in this document should be performed with adult supervision. Likewise, common sense and care are essential to the conduct of any and all activities, whether described in this document or otherwise. Parents or guardians should supervise children. Rock-it Science assumes no responsibility for any injuries or damages arising from any activities.

LasersandMirrorsARock-itScienceLessonFilmedJuly,2009

Title Page of Video

NOTE: This is the transcript of a lesson that was videotaped during an actual Rock-it Science class with real students, not actors. The students’ brainstorming comments are included on the video, but are not transcribed here because they’re not part of the lesson presentation.

Rock-it Science2110 Walsh Ave, Unit FSanta Clara, CA 95050www.rockitscience.org

(c) 2012 Rock-it Science Educationally Useful Programs. All Rights Reserved

http://www.rockitscience.com/

Rock-it Science Teacher’s Guide Lasers and Mirrors --

(No Intro -- Lesson begins with the story)

• Setupamirrornearthebuildingentrancesothatitreflectsaspotofsunlightontheclassroomwall .Tellthestudentstonoticeitslocationandseeifitmoveslateron .

• TellstudentsaboutacarnivalFunHouse,wheretheyhaveweirdmirrors .

• Showstudentsalargeflexiblemirrorandbenditvariouswaystoshowhowitdistortstheimage .

• Askstudentstopredictwhichwaytobendthemirrorinordertomakesomeonelookskinny .

• Eachtimeyoubendthemirroradifferentway,walkaroundwithitsoeachstudentcanseehowtheirownreflectionchanges .

• Storesusemirrorsthatareslightlybenttomakethecustomerslookskinnierintheirdresses .

• Holdafresnellensinfrontofyourfacetomakeyourselflookre-allybig .Askstudentshowyoucouldusethelenstomakeyour-selflookupside-down .

• Tryacoupleofdifferentlensesuntilyougetonethatmakesyoulookupside-down .

• Seeifthespotofreflectedsunlighthasmoved .Askthestudentswhy .

• Putvariousglassandplexiglassobjectsinthepathofthesun-lighttoseeiftheymakerainbows:acylinder,acube,aball,atriangularprism,afacetedcrystal,adiffractiongrating,andaCD .

Demos Recap: “Mirrors and Rainbows”

Upside-down in a Fresnel Lens.

Distorted Reflection

Sunlight on Wall

Rainbow from a Prism.

Diffraction Grating


Experiment Recap: “Lasers and Mirrors”• Giveeachstudenttwoplasticmirrors,about6”x6” .• Theobjectiveistogivethemselvesamillioneyes,cutoffthetopoftheirhead,andmakeatunnelthatlookslikeitgoesallthewaythroughthetabletop .

• Afterstudentsexperimentwiththemirrorsforawhile,tellthemtotrytomakeeveryoneelselookupside-down .

• Thenhavestudentsworkingroupsoftwoormoretocreateamirrorhouse,withtheshinysidesinwards .

• Passoutasheetofpapertoeachstudentandtellthemtodrawabug .

• Havethemusetheirtwomirrorstomakeonebugbe-comefivebugs .Theydothisbyholdingthemirrorsupliketheopenpagesofabook .

• Turnofflightsandshinealaserpointerintoeachstudent’spairofmirrors,makingpatternsoflightasthestudentslowlyopensandclosesthemir-rors .

Multiplying a Bug.

Experimenting with Mirrors

Making a Mirror House.Everyone looks upside-down.

Equipment List: “Lasers and Mirrors”


Items needed for Instructor:

• Mirroronatiltingstandupframe(shavingmirror),about6”diameter

• Mirror,flexible“fun-house”style,about2ftx4ft• Lenses,Fresnel(2)• Prism,Triangular• PlexiglassShapes--cylinder,cube,sphere• CrystalSphere,Faceted,about2”• DiffractionGrating,about8”x10”• CD• LaserPen

Items needed for Students:

Consumables (per student):

• Paper,white,1sheetOther:

• Mirrors,plastic,6”x6”,2perstudent• Markers,ColoredPermanent

Prep Work:

• Cleanthemirrors .• Checkbatteryinlaserpen .

Cylinder & Sphere Cube & Faceted Crystal

Triangular PrismDiffraction Grating Large Flexible Mirror

Story Recap: “The Ghost in the Gold Mine”


Part 1:

• JackandJillboughtahauntedhousenearadesertedgoldminesotheycouldseeaghost .

• Thefirstnight,theyheardaghostcomeclunkingupthestairs,buttheycouldn’tseeit .Thefootstepswentthroughthelivingroom,intothekitchen,openedacupboard,acookiefloatedout,andabitewastakenoutofthecookie .

• JackandJillranandhidintheirbedroom,buttheghostfollowedthem,sotheyhititwiththeirpillows .

• Theghosttoldthemtostop,hedidn’tlikeit .• Jackpouredwaterontheghostsohecouldseeit .• Thentheghostwentdownstairs,satonthesofa,andreadthenewspaperuntil4am,thenwalkedoutthefrontdooranddisappeared .

• JackandJill’sGrandmalivesnearthemine .Theytoldhertheywantedtogetridoftheghostbecauseitwokethemupeverynight .

• Grandmasaidtheyneededtofollowtheghosttofindoutwhereitlives .Thentheycouldmaketheghostgoawaybysprinklingpepperonhishead .

Story Quick Recap (cont.)


Ending:

• JackandJillgotagophertodigaholedownthroughthemountain,buttheholedidn’tendupintherightplace,sothesundidn’tshineperfectlythroughit .

• TheycalledtheAcmeStoreofEverythingandorderedabunchofmirrors .

• Theybouncedlightfrommirrortomirrorandhittheghost,anditfadedaway .Allthatwasleftwashismustache .

• JackandJillfollowedtheghostandfoundoutthathelivedwaydowndeepintheoldmine .Theysprinkledpepperonhishead,butitdidn’twork .

• ThenGrandmatoldthemtosprinklesaltontheghostinstead .Theytriedthat,butitdidn’tworkeither .

• ThenGrandmatoldthemtheyhadtomakethenoondaysunshineontotheghost,andthenhewouldgoawayandnevercomeback .

• Buttheghostwasdeepunderground .• ThegoldmineisownedbyEvilMisterFred,andtheghostisEvilMisterFred’sgreat-great-great-grandpa,sohehasahatandamustache .


Story: “The Ghost in the Gold Mine”Transcript: (NoIntroduction--Lessonbeginswiththestory)

Onceuponatime,therewasahauntedhouse .Thehauntedhousehadarailingsoyoudidn’tfalloffthedeckandbecomeanotherghost .Ithadafrontdoor,andawindow,andithadwalls,andithadaroof,andithadabelltower,andithadachimney,andithadabellinthebelltowerwithadinger,andithadaghost .Thehousewasn’tfloatinginmidair .Thehousewassittingontopofahauntedhill .Andtherewasavalley,there’saforest,andoverinthedistancetherewasagoldmine .Itwasanoldgoldmine,butitwasallbrokendown .Youdidn’twanttogointherebecausethewallswereallcrumbling,andithadcavedininsomeplaces .Sotherewereboardsacrossthefrontwithsomenailsinthem .Andtherewerestoriesaboutthatgoldmine .Theysaidtherewerepeopleinthere,andtheroofcavedinandkilledsomeofthepeople .Andtheghostsofthedeadpeoplestillwanderedthroughthegoldmine .

Andthisbigoldhauntedhousewasforsale .Nobodywantedtolivethere .ButJackandJillheardaboutitandtheysaid,“Wow!Ahauntedhouse .Ialwayswantedtoliveinahauntedhouse .”Sotheyboughtit .Here’sJack .Andhere’sJill .She’sstandingonthechimney .Andtheysaid,“Ihopethere’sarealghosttherebecausewespentallthismoneyforthishouse,andwewanttoseeaghost .”

Sotheystayedtherethefirstnight .Anditgottobemidnight--dong,dong,dong--andthebellswereringing .AndJackandJillsaid,“Idon’tseeanyghosts .Doyouseeanyghosts?There’snoghostshere .”Andthentheyheardfootsteps .Somethingwasgoingclonk,clonk,clonk,clonk,clonk,upthefrontstairs .Andtheylookedouttheirwindowandtheydidn’tseeanybodythere .Andthentheyheardthedooropen--screeeeek!Thedoordidn’treallyopen .Itjustsoundedlikeitwasopening .Andthentheyheardfootstepsrightacrosstheirfrontlivingroom .Andthefootstepswentrightintothekitchen,openedthecupboard,thentheysawacookiefloatoutand--gunk--abitewastakenoutofthecookie .Thenthecookiewassetonthecountertop .Andtheircatwasbehindthestove,andthecatwent“Mreowwww!!”andranaway .AndJackandJillsaid,“Whoa,thatmustreallybeaghost .”

Sotheyranupstairsandhidintheirbedroom .Andtheyheardtheghostcomingupthestairstothebedroom--kadunk,kadunk,kadunk,kadunk .Thentheirdoorknobturned--screeeek--andthedooropened .AndbothJackandJilltooktheirpillowsandwham!--theyhittheairwherethedoorwas .Therewasaghost .Theywentbang,bang,bang--andtheyhittheghost .Theghostsaid,“Stop!Stop!Quithittingme!Don’tdothat!Thathurts!”JackandJillsaid,“What?You’renotatoughghost?”Hesaid,“No,Idon’tliketobehitbypillows .Cutitout!”JackandJillsaid,“Oh .”AndJackwentandgrabbedabigcupofwaterandpoureditovertheghost’shead .Andthewaterwentallovertheghost .

Jack & Jill’s Haunted House.

Grandma’s House near the Gold Mine.


Nowhe’sawetghost .Andhegotjustdisgustedandsaid,“I’vehadenoughofthis .I’mgoingdown-stairs .”Hewentdownstairs,satonthesofa,andreadthenewspaper .Andthen,aboutfouro’clockinthemorning,hewanderedbackoutthefrontdooranddisappeared .JackandJillsaid,“Whoa,whatafunnyghost .”

AndtheytoldtheirGrandmathatnightaboutthatghost .AndGrandmalivesdownherebythegoldmine .Theysaid,“Grandma,wehaveaghostinourhouse .It’sareallycoolghost,buthe’snotverystrong .Hedoesn’tliketobehitbypillows .Andhereallyhatesitwhenwethrowwateronhim .Andwethoughtitwouldbefuntohaveaghostinthehouse .Butnightafternight,hewakesusupandwecan’tgetanysleep .Doyouknowhowtomakethatghostgoaway?”

AndGrandmasaid,“Well,yeah .Don’tyouguysknowhowtomakeaghostgoaway?Everybodyshouldknowhowtomakeaghostgoaway .Don’ttheyteachyouthatinschool?”AndJackandJillsaid,“No .Theydidn’tteachusthatinschool .”AndGrandmasays,“Why,there’sonlyonewaytomakeaghostgoaway .Yougofindhimwherehehidesatnight .Whenheleavesyourhouse,youfollowhim,andgoseewhereheis .Andyoushakesomebrandnewpepperonhishead--shake,shake,shake,shake,shake .Andthatghostwilljustgopoof!Andhe’llneverbotheryouagain .”JackandJillsaid,“Well,thatsoundsprettyeasy .Wecoulddothat .”

Sothenextnight,theghostcameanddidthesamethingasbefore .Andthenhewentoutofthehouse,downthestairs,downthehill,overtheriver,throughthewoods,pastGrandma’shouse,andintothegoldmine .JackandJillsaid,“Ooooh,goldmine--middleofthenight .Itcouldcollapse .Wecoulddie .”Buttheygottheirpepper,andtheyweregoingtogoonwithit .Sotheyfollowedtheghost,downdeep,deep,deepintothegoldmine .Andtheghostcamecleartothebottomwheretherewasabigchamber,anditsatontheground--there’stheghostsittingontheground .Andtheghostsatthereandtwiddledhisthumbs .AndJackcameupandsaid,“Hi,ghost!”andputpepperalloverhim .Andtheghostsneezed,“Ah-choo!Stopthat!”Andnothinghap-penedtotheghost .JackandJillsaid,“Aww,thatGrandmatrickedus .”

Sotheywentbackhomeandwenttosleep .Nextday,theysaid,“Grand-ma,thatdidn’twork .Weputpepperontheghost,andtheghostdidn’tgoaway .”Grandmasaid,“Ohh,Imusthavegottenmixedup .Letmecheckmybook .”SoGrandmalookedinherbook,andshesaid,“Ah,sillyme!You’renotsupposedtoputpepperontheghost’shead .You’resupposedtoputsaltontheghost’shead .”AndJackandJillsaid,“Oh,boy,thisbetterwork .We’rereallygettingtired .”

Sothenextday,samething .Theyfollowedtheghostovertheriver,throughthewoods,pastGrand-ma’shouse,intothegoldmine,cleartothebottom,andtheyputsaltontheghost .Andtheghostsaid,“Whatareyoudoingthatfor?Idon’tlikesalt .Don’tputthatonme .”AndJackandJillsaid,“Aw,thatGrandma .Shedidittousagain .”Ofcourse,theywentbacktoGrandma,andsaid,“Grandma,you’vebeentrickingus .There’snowaythatthat’sgoingtoworkwiththisghost .”Grandmasaid,“Well,Ijustwantedtoseeifyouwouldactuallypullitoff .Buthere’stherealwaytodoit .Allyouhavetodois

The Ghost in a chamber deep inside the Gold Mine.


makesunlight--whenthesunisatitshighestpointinthesky,rightatnoon,sunisstraightupintheskylikethat--makethatsunlightlandontheghost .Andtheghostwillnevercomeagain .”AndJackandJillsaid,“Okay,that’sgoingtobetough .Theghostisinadeepholeintheground .Hmm .”Nowifyou’reJackandJill,andyouwantedtogetridofthatghost,whatwouldyoudo?

[Student: Is Evil Mister Fred in this story?]No,hewasn’tinthisstory .ThisstorywasinventedbeforeEvilMisterFredwasinvented,becauseI’vebeentellingstoriesforalongtime .Wecouldprobablystickhimsomewhereintheending .WhatifEvilMisterFredownsthemine?AndwhatiftheghostisEvilMisterFred’sGreat-great-great-Grandpa?Wecoulddothat .We’dhavetoputamustacheonhim .We’llputamustacheontheghostguy .Andwe’llputahatonhim .There .There’sEvilMisterFred’sGreat-great-great-Grandpa .

The Ghost is actually Evil Mister Fred’s Great-great-great-Grandpa.

Imagination and Brainstorming Time[Students make suggestions](THEREARENOWRONGANSWERS!Whatevertheysay,youshouldreply:“That’sagoodidea,”“Theymightdothat,”etc .Afterbrainstorming,proceedwiththeexperi-ments,thenfinishthestory .)

We’llleavethisToBeContinued . . .

Demos: Mirrors and RainbowsWe’regoingtodosomeexperimentswithlasersandmirrors,andweneedsomesunlightforourexperiment .We’regoingtoputamirroroutsideandseeifwecangetsomelighttoshineinside .[Shines a spot of reflected sunlight onto inside wall of classroom.]We’regoingtousethesunlight .Youseewhere

thedotis?Memorizethatspot .Wewanttoseeifthedotisstillthereinabouttwentyminutesfromnow .

WhenIwasyourage,wecouldgotoSantaCruz,andtherewasaFunHousethere .InsidetheFunHouse,therewasabigwoodendisk,abigcircle,aboutasbigasthistable,butround .Anditcouldspin .Andtherewasateenagertherewithaknobthathecouldturntomakethetablespinfasterorslower .Andhe’dsay,“Okay,everybodyon!”Andwe’dalljumponthisbigtable .Andhe’dsay,“Ready?Herewego!”

Tiltable Mirror reflects sunlight from the doorway onto the wall of the classroom.

Sunlight reflected onto classroom wall.


He’dturnitonandthetable’dstartspinningreallyslow .Andthenitwouldgofaster,andfaster,andfaster,andfaster,untilallthekidswouldgobadoomp!andfalloff .Andtherewasabridgefromoneplacetoanothermadeoutofropes .Andthebridgewouldgoupanddown,andbackandforth,andshakethiswayandthatway,andthey’dknockyouoffthebridge .Andthebestpartofitwasawholebunchofweirdmir-rorscalledFunHousemirrors .They’rekindoflikethisstuff .Now,youcanseeyourselfinthismirror,right?Youcantellthat’sprettymucharegularmirror .Now,ifIwantedtomakeyou,say,tallandskinny,Icanbendthismirror .ShouldIbenditoutwardsorinwards?Howmanyvoteforoutwards?Howmanyvoteforinwards?Okay,it’sabouteven,soI’mgoingtodooutwardsfirst .Areyoutallandskinny?[Students: No.]Isthisaminion-maker?Okay,thatwasoutwards .

Nowwe’regoingtogoinwards .Nowareyoutallandskinny?[Student: It’s upside-down.]Areyouupside-downandtallandskinny?[Students: No.]Well,let’stryitlongways .I’mgoingtopoochitoutwards .[Student: We look so skinny!]NowI’mgoingtopoochitinwardsalittlebit .Areyouthesameasbefore?Sowecanchangehowyoulookwithamirror .Now,supposeyouownedastorewhereyousoldexpensivedressestooldladies .Andyoucouldputanymirrorsyouwantaroundthestore .Wouldyouputmirrorslikethisfortheoldladies?[Students: No.]Wouldyouputmirrorslikethatforthem?[Students: No.]Wouldyoudomirrorslikethisforthem?[Students: No.]Wouldyoudomirrorslikethat?[Students: Yes.]Yeah .Ifyouwanttosellalotofdress-es,youshouldprobablyusemirrorslikethis .Andifyougotosomestores,youmightfindthemirrorsareslightlybentoutwardssotheladieslookskinnierintheirexpensivedresses .Prettyclever,huh?Yeah,thenwhentheygethometheysay,“Whathappened?IgainedtwentypoundssinceIleftthestore .”

There’sotherwaystomakethingslookweird .Youcanmakethingslookreallybeautifulorreallyhand-somewiththis[holds a fresnel lens].IfIputitinfrontofmyface,I’llbecomeextremelyhandsome .You’llsay,“Whoa,amoviestarintheplace!Wow,thatissocool!”Hereyougo--amoviestar[holds lens in front of his face, making it look very large and distorted].Wasmyheadrightsideup?[Students: Yes.]Okay,andtomakemyheadupside-down,shouldIturnthemir-rorupside-down?ShouldIturnitthisway?No?HowaboutifIgolikethat?[Holds lens at arm’s length in front of face.]AmIrightsideuporupside-down?Weneedtheotheronetogoupside-down .[Tries using two lenses at once.]Isthatoneupside-down?[Tries a different lens.]Oh,thatoneisanupside-downone .AmIupside-downnow?[Students: Yes.]Youguysareupside-down .Sowecandistortyouwithmirrors,wecandistortyouwithlenses,thereareallkindsofwaystomakepoeplelookverystrange .

Andwe’regoingtodosomeexperimentswithsomemirrors .Wehavemirrorslikethese[holds up a 6-inch square mirror].They’replastic,sodon’trubthemoneachothertoomuchorthey’lljustgetscratched .They’reslightlybendable .Andwe’regoingtogiveeachofyoutwomirrors,andyou’regoingtodosomeexperimentswiththemandseewhathappens .

Flexible Mirror can be bent to distort the image.

Upside-down with a Fresnel Lens.


Sinceoursunisstillhere,isoursunstillinthesamespotthatitwasbefore?[Students: No.]Okay,we’vegotsomesunshiningonourwall .It’smoved .Howdidthesunmove?[Students offer explana-tions.]Yeah,theEarthorbitsaroundtheSun .AndtheEarthspinsonitsownaxis .AndastheEarthturns,theSunmovesonourwall .I’mgoingtoturnoffthelights,andI’mgoingtoputstuffinthatsun-light .We’llputacubeinthere .Wewanttoseeifwefindanyrainbows .We’llputacylinderinthereandseeifthatmakesanyrainbows .We’llputaballinthereandseeifthatmakesanyrainbows .We’llputacrystalinthereandseeifthatmakesanyrainbows .Andwe’llputaprisminthere--there’satriangularprismhere--andseeifthatmakesanyrainbows .

Okay,here’sthecylinderinthesunlight .Canyouseeanyrainbowcolors?HowaboutifIdoitend-wise?Doyouseeanyrainbowsthatway?[Students: No.]Sowe’rerainbowless,right?Okay .Here’sacube .Anyrainbowswithacube?Okay,norainbowswithacube .Herecomestheball .Anyrainbows?Itdoesn’tdoanythingatall?Howaboutatriangle?[Students: Yes.]Ah,there’sonethere .Okay,that’satriangularprism .We’lltryacrystal .[Students: Yes! Millions!]Nowwehaveahologram .Thisisahologramcalledadiffractiongrating .[Students: Yes!]We’regoingtogetaCDjusttoseeifaCDdoesanything .WillwegetrainbowsfromaCD?[Students: Yes.]We’llfindout .[Students: Yes!]So,ifyouhaveabunchofCDsinawindowathome,youcanhaverainbowsalloveryourhouse .

Rainbows from Faceted Crystal.

Rainbow from Triangular Prism.

Rainbow from Diffraction Grating.

Rainbow from a CD.


Experiment: Lasers and MirrorsOkay,we’regoingtogiveyoutwomirrors .Andtheobjectiveistogiveyourselfamillioneyes,cutoffthetopofyourhead,andmakeatunnelthatlookslikeitgoesallthewaythroughthetabletop .[Passes out mirrors, and students experiment with them.]Trytomakeeverybodyelseupside-down .Workwithoneormoreneighborsandcreateamirrorhouse .Puttheshinysidesinwards,thenlookinthroughtheside .

Building a mirror house.Making other people look upside-down.

[Passes out a sheet of paper to each student and provides col-ored markers.]Whenyougetapieceofpaper,you’regoingtodrawabug .Youcandrawonebug,andthenyou’regoingtouseyourmirrorsandtrytomakefivebugs .

Nowwe’regoingtoblindyourbugswithalaserwhileyouholdyourmirrorsup .[Turns off lights, then shines a laser pointer into each stu-dent’s pair of mirrors, making patterns of light as the student slowly opens and closes the mirrors.]

Multiplying a Bug.

Laser patterns.

End of Lesson

If y0u have questions about this lesson, please ask them through the online Teacher Support Forum on our web site.


End of Story * DO NOT * present this part of the lesson until after the experiments!JackandJillaretryingtogetridoftheghostatthebottomofthemine .Grandmatoldthemtotrypep-per,shetoldthemtotrysalt,didn’twork .Thenshesaid,“Youhavetodrillaholeinthereandmakethesunshinerightontheghost .”Sotheygotagopher,andthegopherdugaholethroughthemountain,buttheholedidn’tendupintherightplace .Andthesunlightdidn’tshineperfectlythroughit,anditdidn’thittheghost .Andtheysaid,“Oh,no .Toobad .”SotheycalledtheAcmeStoreofEverythingandtheyorderedabunchofmirrors .Andtheybouncedthelightfrommirrortomirror--boing,bo-ing,boing,boing,boing,boing,boing--andhittheghost .Andtheghoststartedtofadeaway .“Nooo,pleeease,aaaaaahhhh!”Hegotdimmer,anddimmer,anddimmer,untiljusthismustachefelloff .Andthatwastheendoftheghost .

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teacher’s guide for: lasers and...

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