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WHAT'SGOINGONHERE,BEAKMAN?STUDYGUIDEv.29-8-16
PERSISTENCEOFVISIONDEFINITION:
PERSISTENCEOFVISIONistheopticalillusionwhereuponmultipledifferentimagesblendintoasinglemovingimageinourminds.Becauseoureyesretainimagesforashortperiodoftime,wecanperceivemovementbetweenimages.It’sbelievedtobetheexplanationforhowweseemovies.
INTHESHOW:Beakmanswingsaballwithflashinglightsthatdemonstratespersistenceofvision.QUESTION:HeyBeakman,howdomovieswork?
ANSWER:Toansweryourquestion,firstonemustknowthatlightbounces,andthat’showweseethings.Let’ssayyouarelookingatanorange.Lightbouncesofftheorangeandgoesdirectlyintoyoureyes.Youreyesandyourbrainmakeapictureoftheorange,andthenyourbrainputstogetherthatimagewithpastexperiencesofseeingorangesandperceivesitasanorange.Butwhataboutmovies?Howdotheywork?Let’ssayyouarelookingatamovieofanorangebeingeatenbyamonkey.Thelightfromthemoviegoesdirectlyintoyoureyes.Youreyesholdeachpieceofthemonkey-eating-the-orangemovingpicturesfor1/30thofasecond,longenoughforyourbraintoputeachofthosepiecestogetherintoonemovie.Thiswaythatyoureyesholdlightfor1/30thofasecondiscalled:PersistenceofVision. Nexttimeyougotothemovies,remember:whatyouareseeingisflashingpictures.That’swhatmoviesare:flashingpictures.Butbecauseyoureyesholdlightfor1/30thofasecond,youseemoviesasonemovingpicture.
INTERNETHere’saYoutubevideoonhowtobuildasimpleNewton'sdisk,whichdemonstratespersistenceofvisionANDhowwhitelightismadeupofmanydifferentcolors.https://www.youtube.com/watch?v=cPHOCysZS2kHere’salinktoanappforyourphonethatcreatesaNewton’sDischttps://play.google.com/store/apps/details?id=com.avoupavou.newtonsdisc&pageId=107328086152208664153
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CLOUDINABOTTLEDEFINITION
CLOUD1. amassintheskythatismadeupofmanyverytinydropsofwaterandcanbewhite
orvariousshadesofgrey2. alargeamountofdust,smoke,orothertinyparticlesthataresuspendedintheair
INTHESHOW:Beakmancreatesanactualcloudinabottle,showinghowcloudsareformedbymoistureadheringtodust.QUESTION:HeyBeakman,whatisdust,andwhatdoesithavetodowithclouds?
ANSWER:Dustismadeupofanymaterialthatisveryfine,i.e.verytinyparticles.Forexample,bitsofsoilorfabricorwoodorashesorevenmaterialsfromspacecanmakeupdust.Youreadthatright!Scientistshaveexamineddustandhavefoundthatsomedustfloatingaroundorsittingonthingsactuallycontainstinybitsofmeteors,stars,andotherstufffromspace.Acloudweseeintheskyisformedwhenparticlesofwateroricesticktodustparticlesthatarefloatingintheair,usuallywellabovethesurfaceoftheearth.Waybackin1803,anEnglishscientistnamedLukeHowardnamedthreebasictypesofclouds:cirrus,cumulus,andstratus.Therearemanyvariationsofthesebasiccloudtypes,butwestillusethesetermstodescribecloudsweseeinthesky.
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Cirrusclouds
Highcirruscloudsareseparate,delicate-appearingclouds,mostlywhiteincolor,andmadeupoficecrystals.Theyoftenlookliketuftsorbunchesoffeathers.Therearesubgroupsofcirrusclouds,too:cirrocumulus(mackerelsky),madeupofsmallwhiteflakesorverysmallglobsthatarefoundinlinesandgroupsandripples;andcirrostratus,athinwhitishsheetcloud,whichsometimesmakestheentireskylookmilky.Thesecloudscancreateahaloaroundashiningmoonorsun.
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Cumulusclouds
Intermediatecumuluscloudshavesubgroups,too:altocumulusclouds,areflatpatchesofglobularmassesthatcanbeseeningroups,waves,orlines;andaltostratusclouds,whichlooklikethickcirrostratuscloudsbutdon’tmakeahalowithshiningmoonandsun.Insteadtheycanonlyletanoutlineofthemoon,ifnothideitcompletely.Thenthere’satypeofthickcumuluscloudthatisseeninfairweatherandoftenlookslikeastalkofcauliflower,andthethunderstormcloud,cumulonimbus,bigthickmassesthatresemblemountainsortowersandsometimesreachthestratosphere.Thesecumulonimbuscloudscreaterainandsnowshowers,hailstorms,andthunderstorms.
Cumulonimbusclouds
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Stratusclouds
Stratusclouds,whicharelowclouds,haveanumberoftypes,too:stratocumulus,acloudlayerorpatchescomposedoffairlylargeglobularmassesorflakes,softandgraywithdarkerparts,arrangedingroups,lines,orrolls,oftenwiththerollssoclosetogetherthattheiredgesjoin;stratuscloudsoftenlooklikefogbutdon’treachtheground;andnimbostratusclouds,alayerofdarkgreycloudsofnoparticularshapeandoftenproducerainandsnow.
Theonethingallthesecloudshaveincommonisthattheyareformedbycombinationsofdustandtinybitsofwaterandice.
RESOURCES:
Here’sagreatsiteaboutcloudswithpicturesofdifferenttypesofcloudsandsomesimplecloudrelatedexperimentsyoucandointheclassroom.http://www.weatherwizkids.com/weather-clouds.htm
Greatphotosofdifferenttypesofclouds:https://scied.ucar.edu/cloud-image-gallery
EDIBLEBUGSDEFINITION
EDIBLE:Suitableorsafetoeat.BUGS:Youknowwhatbugsare!lolINTHESHOW:BeakmandescribesandillustratessomeoftheinsectspeopleeatinMexico.
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QUESTION:HeyBeakman,aretherereallypeoplewhoeatbugs?
ANSWER:Youbet!Somestudiesshowthat80%ofthepeopleintheworldincludeinsectsintheirdiets.Andthereareatleast1,700speciesofedibleinsectsintheworld.
CookedcricketsforsaleinaThaimarketWhy,youwonder,ohwhywouldpeopleputbugsintheirmouths,chewthem,andthen(gulp)swallowthem?!?!?Inthedaysofearlyhumans,insectswereanimportantpartofdietsbecausetheyweresomucheasiertocatchthanlargeranimals.Peopleacrosstheworldeatbugstodaybecauseittakesalotlesswaterandfeedtoraiseinsects,andmostofthemarealothealthiertoeatthanlargeanimals,too,becausetheyarelowinsaturatedfatandfilledwithvitaminsandminerals.Thereareplacesintheworldwhereinsectsarefarmedandthensoldinmarkets.Inothercultures,theinsectsaregatheredfromthewildandthenspiced,cooked,anddownthehatchtheygo!YearsagoinJapan,wasphunterswouldactuallycatchawasp,tyingalongsilkthreadtoitsbody,followedthewasptoitsnest,andcaptureabigloadforlunch.
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Escamolesareanteggs
PancakesmadefromsilkwormsThetypesofedibleinsectsthatwecanfindinNorthAmericaincludesomevarietiesofcrickets,grasshoppers,locusts,termites,Junebugs,ants,centipedes,scorpions,mealworms,wasps,bees,andcaterpillars.Butpleasedon’trushoutsidenowandstuffahandfulofbugsintoyourmouth!Someinsectsarenothealthyforhumanstoeat,andmanyprobablydon’ttastesogood.INTERNEThttp://www.secretsofsurvival.com/survival/top-10-edible-insects.htmlGirlMeetsBug:Agreatsitewithplentyofinfo,links,andevenrecipesforscarfingdowninsects.https://edibug.wordpress.com/orherFacebookpage:https://www.facebook.com/GirlMeetsBug
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OPTICALILLUSIONSDEFINITIONS:
OPTICALOforrelatingtosight,particularlyinrelationtolight
ILLUSIONSomethingthatappearstoberealortruebutinactualfactisnotreal,oritisfalse.
OPTICALILLUSIONAnopticalillusionappearstobedifferentthanwhatitreallyis,i.e.somethingthatyouseebutisnotreallythere,orisnotwhatitlookslike.Thereareanumberofdifferentkindsofopticalillusionsthattrickourbrainsfordifferentreasons.Andscientistscannotexplainhowcertainopticalillusionsactuallywork.INTHESHOW:Beakmanholdsuptwoflatmodelsofroadsthat,whenheldindifferentpositions,appearstobedifferentsizeswheninfacttheyareboththeexactsamesize.QUESTION:Hey,Beakman,what’sanopticalillusion?Andwhat’supwiththesepictures?
ANSWER:Oureyesandmindshavelearnedtoidentifyvariouspatternsandrelationshipssothatwecandeterminewhatisgoingonaroundus.Butoureyesandmindscanbefooledbypatternsthatdonotnormallyoccurinourworld.Soourbrainscangettricked,andwecanseesomethingthatisnotrealorcorrect.Herearesomeexamples:
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Thegreylinesbetweentherowsofboxesareactuallystraightandparalleltoeachother,eventhoughtheylookwavy.Don’tbelieveme?Placearulerupagainstthehorizontallines,andyouwillseethattheyareindeedstraight.
Ourbrainmakesdecisionsaboutthesizeofsomethingbylookingatstuffaroundit.Inthecirclesontheleft,thecentercircleissurroundedbybiggercircles.Soitlookssmall.Inthecirclesontheright,thecentercircleissurroundedbysmallercircles.Soitlooksbig.Yourbrainthinks:Small.Big.Small.Big.Buttheyareactuallythesame.Don’tbelieveme?Measurethem.
SUBLIMATIONDEFINITION
SUBLIMATIONThechemicalprocesssublimationisthetransitionofasubstancedirectlyfromthesolidphasetothegasphasewithoutpassingthroughtheintermediateliquidphase.Thereverseprocess–thetransitionofagasintoasolid,skippingtheliquidphase–isalsocalledsublimation.
INTHESHOW:Beakmanputssomedryiceintoabucketandthenpoursabunchofsoapywaterontopofit.Amessensues!QUESTION:HeyBeakman,doesallicemelt?
ANSWER:Nope!Allowmetoexplain…
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Dryiceisfrozencarbondioxide,thesamestuffthat’sinthebubblesinsoda.Butdryicecarbondioxideisfrozenintoasolidat109degreesbelowzeroFahrenheitand78.5degreesbelowzeroCelsius…cold!Whensoapywaterisdumpedontopofthedryice,thedryicedoesnotmeltintoaliquidlikeordinaryicewould.ThesolidcarbondioxidegoesdirectlyfromasolidmassintoagasorvaporinaprocesscalledSUBLIMATION.Andthatgascombineswiththesoapinthewatertocreatealotofbubbles,whichmakeagiantmessalloverthestage.FURTHERRESOURCESAbunchofdryicedemonstrations!https://www.youtube.com/watch?v=QhTekm5NdiE
BEACHBALLANDLEAFBLOWERDEFINITIONS
BERNOULLI'SPRINCIPLE:Whenthespeedofafluidincreases,itspressurewillfall.
PRESSURE:Theforcethatoneareaofgas,liquid,orsolidexertsonanother.
FLUID:Aliquidoragasthatflowseasilyandconformstotheshapeofitscontainer,likewaterinaglassorairinaballoon.INTHESHOWBeakmanfiresupaleafblowerandplacesabeachballinthestreamofrushingair.Itstaysthere.QUESTIONHeyBeakman,ifthere'ssomuchairpushingagainstit,whydoesn'ttheballkeepgoingup?Orwhydoesn'titflyoffacrosstheroom?
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WhenwewalkaroundonEarth,weareatthebottomofanoceanofair.Thatair,theEarth'satmosphere,ispressingonusandeverythingaroundusallthetime,eventhoughwearen'tawareofit.Turningonaleafblowerstartsastreamoffastrushingair,andfastrushingaircreateslowerairpressure.Ifyouplaceabeachballintothatstream,itwillstayintheareaoflowerairpressurebecausethehigherpressureairallaroundthestreampushesontheballfromthesidesandkeepsitinplace.ThiswaythatfastrushingaircreateslowerairpressureiscalledBernoulli'sPrinciple.Bernoulli'sprincipleappliestoallfluids,includingairandwater.Itisthereasonthatairplaneswork.Thecurveontheuppersideofanairplanewingcausestheairrushingoverthewingtomovefasterthantheairrushingunderthewing,sothereislesspressureontopandmorepressureunderneath,givingthewinglift.
Airflowoveranairplanewing,seenincrosssectionYoucanalsoblameBernoulli'sprinciplewhenthishappens:
Aeronautics: An Educator’s Guide EG-2002-06-105-HQ26
Discussion
Assessment 1. Have a classmate observe the paper tongue and record whathappens. Switch roles.
2. Write a paragraph or draw a picture to describe what happensto the paper tongue.
3. Write a paragraph or draw a picture to tell how airplane wingsare similar to the paper tongue.
1. Why does the tongue move when you blow gently through themouth? What happens when you blow harder? The curvedsurface of the tongue creates unequal air pressure and a liftingaction. Blowing harder will cause the tongue to move up anddown faster.
2. Attach a lightweight streamer to a fan or air conditioning vent.Ask the students to observe and describe what happens. Howdo the streamers relate to this activity? The same force movesthe tongue and streamers. Lift is caused by air moving over acurved surface.
3. What are some other common examples of Bernoulli'sprinciple? Flags waving, sails, an umbrella that becomesimpossible to hold in a strong wind.
Extensions 1. Experiment with different tongue lengths.
2. Encourage the students to be creative with the designs on thebags – faces that say something about who they are, or whothey want to be, maybe the face of a friend, relative, orclassmate. The designs may also be abstract, or not human;consider holiday themes.
low pressure
high pressure
low pressure
high pressure
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Theairblowingoverthetopoftheumbrellagoesfasterthantheairblowingunderneaththeumbrella,sothepressureunderneathishigherthanthepressureontop,andtheumbrellaturnsinsideout.HerearetwosimpleexperimentsyoucandowithapieceofpapertoexperienceBernoulli'sprincipleatwork.Youwillneedonesheetof81/2"x11"paper.Foldthepaperinhalfandcutalongthefoldsoyouhavetwopiecesthatare81/2"x51/2".LEVITATINGPAPERTakeoneofthehalf-pieceofpaperwithbothhandsandholditrightbelowyourmouth,likethis:
Now,blowhard.Whathappens?CanyouexplainthemovementofthepaperusingBernoulli'sprinciple?TWOPAGESHoldtwohalf-sheetsofpaperinfrontofyoulikethis,andblowbetweenthem.
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Now,whatdoyouexpectwillhappenifyoublowbetweenthesetwopages?Willtheymoveapart,orsticktogether?Tryit.CanyouuseBernoulli'sprincipletoexplainthemovementofthetwopages?QUESTION:So,what'sgoingonhere,Beakman?
ANSWER:Whenyoublowacrossthetopofthepaperinthefirstexperiment,youcreateanareaoflowerpressure,andthehigherpressureairunderneaththepapercanpushthepaperup.Whenyoublowbetweenthetwopages,youmightexpectthemtobepushedapart,butagain,therushingairbetweenthepagescreatesanareaoflowerpressure,andthehigherpressureofthestillaironeithersidepushesthetwopiecesofpapertowardeachother.RememberthattheconstantpressureofEarth'satmosphereonusandeverythingaroundusisn'tjustpushingdownfromabove,butfromallsides,evenfrombelow.
QUESTIONSo,whoisBernoulli?
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DanielBernoulli,1700-1782
ANSWER:DanielBernoulliwantedtobeamathematicianlikehisfather,buthisdadinsistedthathebecomeadoctorinstead.Whilestudyingbloodpressure,Bernoullisetupanexperiment.Hepuncturedapipewithasmallopen-endedstraw,andwatchedwhathappenedasliquidflowedthroughthepipe.Higherpressureinthepipecausedmoreliquidtoriseupintothestraw,sohecouldseethatthewhenthewaterinthepipewasmovingfaster,thepressurewasactuallylower.Bernoullididthemathtoshowhowthisphenomenonwasconsistentwiththelawofconservationofenergy.Heinventedtheword"hydrodynamics"forthestudyoffluidsinmotion,andhewroteabookaboutit.
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TitlepageofBernoulli'sbookBernoulli'sfatherwassojealousofDaniel'swork,hewroteabookplagiarizinghisson'sideasandputafakedateonitsoitwouldlooklikeDanielhadcopiedfromhim,insteadoftheotherwayaround.Fortunately,peopleweren'tfooled,andaftermanyyearsoflivinginplaceshehatedandtakingjobshedidn'twant,DanielBernoulligothisdreamjobasaphysicsprofessorinhishometownofBasel,Switzerland.Hewasfamousforhisamazinglecturedemonstrations.OTHERRESOURCES:https://youtu.be/J4WRd7OAt0ALaunchpad:Bernoulli'sPrincipleOn-BoardtheInternationalSpaceStation
AIRZOOKADEFINITIONS
VORTEX:amassofairorwaterthatspinsaroundveryfast.Thepluralisvortices.
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TOROIDALVORTEX:adoughnut-shapedvortexinafluid.Torusisthemathematicalwordforadoughnutshape.INTHESHOW:Beakmanusesavortexcannontoshowthepowerofavortexofair.QUESTIONHeyBeakman,whatisavortexcannonandhowdoesitwork?
Vortexcannonmadefromanoatmealboxandplasticwrap.
ANSWER:Avortexcannonisakindofbucketwitharoundholecutinthecenterofthebottom.Theopenendofthebucketiscoveredwithaplasticorrubbersheet,stretchedandsecuredallaround.BeakmanusesacommerciallymadetoycalledanAirzooka,butyoucanmakeyourownvortexcannonusinganythingfromaplasticcuporbottletoabucket,acardboardbox,orevenagarbagecan.Thebiggerthecannon,thebiggerandmorepowerfulthetoroidalvortexitcanproduce.
Thisoneusesaballoonontheend.Insteadoftappingtheback,youcangentlypullitbackandsnapittoreleasethevortex.
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Here'sareallysimpleandlargeone.Sealalltheseamsofaboxwithtapeandcutaholeinoneside.Thentooperateit,youthumpthesideoftheboxoppositethehole.
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Thisfamilymadeanextra-largecannonfromatrashcan.Tooperateyourvortexcannon,simplytaptheendoppositetheholetoreleaseatoroidalvortex.Youwon'tbeabletoseeit,butyoucanseeitseffect.Tryaimingitatyourfriend'shair,orastackofstyrofoamcups,ahouseofcards,orsomeotherlightweighttarget.Experimentwithdistance.Ifyourcannonhasarubbersheetonthebackend,youmightfindit'sbettertogentlypullitoutandreleaseittoexpeltheair.Tomakeyourvorticesvisible,you'llneedtoaddsomethinglikedustorsmoke.Ifyouhaveafogmachine,youcanfillthebucketwithfogbeforefiringit.Dryiceworks,too.Youcanlightacoupleofincensesticksandcarefullyinsertthemintotheholeofyourvortexcannontofillitwithsmoke.Vortexcannonsworkbestinanenclosedroomwithnoaircurrents.Abreezefromanopenwindoworfromanelectricfanwillcauseairturbulencethatwillaffectthequalityofyourvortices.
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Howdoesitwork?Whenyoutaptheplasticsheet,itpushesaburstofairoutthehole.Mostofitgoesstraightout,butsomeoftheair(andwhateversmokeorfogyouputinthecannon)willgetdraggedbytheedgeoftheholeandpushedbythesurroundingairsothatitcurlsbackintoadoughnutshape.Itkeepsonspinningasitmovesawayfromthemouthofthecannon,andthisspiniswhatkeepsthedoughnutshapetogetherasthevortexshootsacrosstheroom.Also,becausethedoughnutofairisspinning,theairinsideitismovingfasterthantheairaroundit,andthisiswhereBernoulli'sprinciplepopsupagain.Thespinningairinsidetheringisatalowerpressurethanthestillairoutside,sothestillairpressesinontheringfromalldirections,helpingtheringkeepitsshape,andkeepingthesmokein,soyoucontinuetoseethatbeautifulsmokeringsailonby.
QUESTIONWhatcanyoudowithatoroidalvortex,besidesmessingupsomeone'shairfromtenfeetaway?
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ANSWER:Notmuch,really,thoughpeoplehavetried.In1998theUnitedStatesArmyResearchLaboratoryexperimentedwithconvertingamachinegunintoavortexcannonasameansofnon-lethalcrowdcontrol.Theideawastojustknockpeopleover,ormaybetousetheairvortextocarryadye,afoul-smellinggas,oranincapacitatingchemicalstraighttooneortwopeopleinacrowd.Theexperimentwasnotasuccess.Thevortexwasnotstrongenoughtoknockanyonedownfrom100feetaway,andalthoughitcouldcarryagasoradye,itwasleaky,anditendedupspillingstuffoninnocentbystandersbetweenthegunandthetarget.AwastemanagementcompanyinDenmarkhasfoundamorebeautifuluseforatoroidalvortex.TheyarebuildingawastetoenergyplantinCopenhagenthatwillhaveaspecialsmokestackthatblowsasmokeringforeverytonofcarbondioxidereleasedintotheair.Thecompanyseesitasagentlereminderoftheimpactofconsumptionontheenvironment.Theplantitselfwillbebuiltintheshapeofamountainandcanbeusedasayear-roundskislope.
TheAmagerBakkeincineratorQUESTIONCanyoueverseeatoroidalvortexinnature?
ANSWER:Severalvolcanoeshavebeenseenemittingsmokerings,includingMountEtnainItaly.
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MountEtnasmokeringDolphinsandsomewhalesblowbubblerings,whichareakindoftoroidalvortex.Dolphinsenjoyplayingwiththebubbleringstheycreate,sometimessplittingthemintotwosmallerringswiththeirbeak,sometimesbitingthemtobreakthemintoacascadeofnormalbubbles.Theycanmakeabubbleringintwodifferentways.OnewayworksliketheAirzookavortexcannon,justablastofairintothewaterthatformsaring.Thesecondmethodistoswishitstailtostartatoroidalvortexinthewater,andtheninjectairintoit.
Abelugawhalemakesabubblering
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FURTHERRESOURCEShttps://youtu.be/pnbJEg9r1o8Crazypoolvortex.Physicsgirlmakesatoroidalvortexinaswimmingpool.https://youtu.be/LaIzbtc8mHcBuildingBlowsGiantSmokeRingshttps://youtu.be/VbV98Z0QP-kSpectacular,incredible,amazing..rarelyseensmokeringsatMtEtnahttps://youtu.be/wuVgXJ55G6YDolphinBubbles:AnAmazingBehavior|SeaWorld®OrlandoDolphinCove®https://youtu.be/NU6j_w5r-TYHowToMakeSmokeRings--Anicesimplehow-tovideoformakingyourownsmallvortexcannonusingaplasticbottle,aballoon,andincensesticks.http://www.physicscentral.com/experiment/physicsathome/cannon.cfm--Instructionsonmakingavortexcannonfromanoatmealcontainer
THEEND!