LiftingHeavyThings,Revised2016
IntroducingLiftingHeavyThings
Severaldaysbeforebeginningthiskit,haveavailableforchildrentoexploreindependently,abasketofsimpledevices(kitchengadgets)thatyouhavecollected.Includemechanicalobjectssuchasaneggbeater,anoldpencilsharpener,anoldclock,andacanopener,etc.Ø ThechallengeactivitiesforLearningExperiences2,3,5,6,7,and8havebeen
amendedtocorrelatewithkitmaterialsandtobettermeettheNewYorkStateScienceStandards.
• Itissuggestedthatthechallengesandchartsbeconvertedtouseonthe
overheadorbemadeintopermanentchartsthatcanbelaminatedandusewheneveryouusethiskit.
LiftingHeavyThings,Revised2016
LearningExperience#2Fullandhalfpiecesofguttershavebeenaddedtothekit.Thelongerlengthofguttermaybesubstitutedforthemeterstickandtheshorterlengthforthe24”ruler.Therearegreenplasticflowerpotsincludedinthekitthatwillholdwashersandcanbeusedinplaceofthewhiteboxes.Whenusingthegutters,youshouldusethehalfpiecesectionsasfulcrumstogethertomakeoneasintheillustrationbelow.
ShouldyouchoosetodotheHomeSchoolWorksheetattheendofthislearningexperience,arevisedversionisincludedthatemphasizessafetyandworkingwithadultsupervisionwhendoingtheactivity.Asubstitutehomeschoolactivitymaybe,tohavechildrendrawapictureofaleverfoundintheirhomesandwriteadescriptiontellinghowitisused.
twofulcrums puttogether
sideview
LiftingHeavyThings,Revised2016
LearningExperience#3Safetygogglesareincludedforusewiththislearningexperience.Thislearningexperiencehasthreeactivities.Themanualsuggeststhatyousetuptwoidenticalstationsforeachactivity.However,onlyonesetofmaterialsisprovidedwithyourkit.Youmayfinditmoremanageabletohaveonlyonestationperactivity.Inyourkityouwillfindanemptypaintcanwithalidassuggestedinthematerialslistforthislearningexperience.Alsoincludedareacrescentwrenchandsomelagboltsbecausetheycanbeusedassimplemachines.Thecrescentwrenchcanbeusedasalevertoscreworunscrewthelagbolts.Thelagboltfunctionsasaspiralinginclinedplane,asdoesthewormgearonthecrescentwrench.ForSafetyreasonsitissuggestedthatyoueliminatetheuseoftheknifeandcrowbar.Thequarterandcraftstickcanbeusedinbothactivities#1and#2.Whenhammeringnailsintothewooditisbestnothammerthemallthewaydown.Forthethirdstationyoumaywanttouseaheavybook,likeadictionary,asload,the24”ruleastheleverand,theedgeofthedeskasthefulcrum.Ifyouhavearecyclingbin,tryputtingthedictionaryinitandusingapieceofwoodasthefulcrumandlift
theloadwiththemeterstick.Youshouldplantodothislearningexperienceatatimewhenthereisanadultassistantavailable.Youmaywanttorecruitaparentvolunteerora
responsibleuppergradestudentforthispurpose.
Startat24”andworkyourwayup.
LiftingHeavyThings,Revised2016
LearningExperience#5Ø Ifyouchoosetousethemetersticksinplaceoftheguttershere,itisnecessary
totapetwoofthemtogethertodoublethewidth.Ø Rubberbandsmaybesubstitutedfortapeonthebox*thatthestudentsneedto
continuallyopen(tapeandun-tape)whenworkingwithweights.Anothersuggestionistosubstitutethegreenplasticflowerpotswhichareprovidedinyourkit,inplaceoftheboxthatwouldneedtocontinuallybeopened.Youcanuseanopened,large,paperclipfor‘S’hooks.
Springscales,whichareincludedinthiskit,canbeusedasanalternativewaytomeasureforce.Thoughtheycanbeusedinmanylessons,theyworkespeciallywellwiththeinclinedplanes.Youmaywanttoleavethespringscaleandwashersinanareawherethechildrencanindependentlyinvestigatethemandrecordtheirobservations.*Boxesareconsideredconsumableitems.Onceassembledwiththestring,youmaybeabletokeepthemintactandreplacethemasneeded.Youshouldbeabletosavethemfromyeartoyear,makingsetupeasier.
SealedBox6weights
OpenedPaperclip
Flowerpot6weights
OpenedPaperclip
LiftingHeavyThings,Revised2016
LearningExperience#6Cclampsareincludedtouseaspulleys.ThelargeCclampfitsontopofthedoorreplacingthe‘S’hook,(seemanualp.115.)Arecycledlaundrydetergentbottle,whichcanbefilledwithwater,maybeusedasaloadforthestudents’toexperiencetheusefulnessofapulley.ThesmallCclampsareusedforstudents’deskswiththeboxesandweights.Whenusingthemeterstickwiththepulleyitishelpfultotapeitdownsoitwon’tslidearound.Whenworkingwiththepulleysystems,youmayneedtousetwopaperclipsopenedtoform‘S’hooks.Seeillustrationbelow.
Ø Trythisactivitytofurtherillustratetheuseofapulley.
• Youwillneedtwobroomsandalengthofrope.
o Havetwostudentsholdtwobroomsabout18”apartfromandparalleltooneanother.
o Tieoneendofaropetothefirstbroomhandlethenlooptheropearoundbothbroomsonetime.
o Haveathirdstudentslowlypullthelooseendoftheropewhiletheothertwostudentsattempttokeepthebroomsapart.
o Repeattheprocessloopingtheropetwotimesandthenthreetimes.JournalActivity
Studentsshoulddescribewhathappenedasmoreloopswereadded.
LiftingHeavyThings,Revised2016
LearningExperience#7Thethree-partpulleysystemprovidesachallengeforstudents.Afterbrainstormingwithstudents,perhapsintheformofdrawingsandquestions,youmaywanttoprovideanillustrationofthepictureonpg.131ofyourteachers’guide.Thestudentscanthenassembleandinvestigateathree-pulleysystem.
Ø PredictandTest
v Whatistheadvantageofusingpulleys?
ChallengeActivitySharingTheLoad
AnEmbeddedAssessment
• Thisactivitycanbedoneasagrouporinalearningcenter.
MaterialsRequired
• Cclamp• 2stringsabout1meterlong.BothbeginningattheCclamp• 2pulleys
o Usingthepulleysystemillustratedbelow,predicttheamountofforcerequiredtoliftaheavyobjectsuchas2litersofwater,whichhasamassofapproximately2000grams.
o Afterrecordingyourpredictioninyourjournal,usethespringscaletomeasuretheactualforce.
o CompareyourfindingstoyourpredictionsJournalQuestions
1. Whenusingapulleysystemsuchasthistoliftaheavyload;a. Whataretheadvantagesb. Whatarethedisadvantages
2. Whataresomeofthewaysthatyoucouldconnectadditionalpulleystothissystemtomakeiteveneasiertoliftheavyobjects?
a. Recordyourpredictionsaboutthenewarrangementsandtestthemusingthespringscales
LiftingHeavyThings,Revised2016
LearningExperience#8EmbeddedAssessment
Inadditionto,orinplaceofthesuggestedactivityyoumaychoosetousethefollowingactivity.Anillustrationofanautomechanicshopwillbefoundonthenextpage.Feelfreetocopythisdrawing.Thisactivitycanbedoneindividuallyorinsmallgroups.Studentsworkingtogethershouldlatergiveanoralpresentationoftheirideastotheclass*
Ø Tasks1. Nametheobjectbeinglifted2. Identifythesimplemachinebeingusedtolifteachobject3. Cantheworkbemadeeasier?
a. Explainormakeadrawingtoshowhow
Bonus:Canyouthinkofothersimplemachinesthatmightbeusedinanautorepairshop?*Ifyoufindanotherwaytousethisillustration,pleaseshareyourideaswithusontheevaluationsheetthatcanbefoundatthefollowinglink;Firsthandlearning.org
LiftingHeavyThings,Revised2016
LiftingHeavyThings,Revised2016
OverviewThislessonprovidesstudentswiththeopportunitytoexperiencethemechanicaladvantagepossiblebyusingcertainpulley-ropeconfigurations.Studentswillengageinvestigationofavarietyofpulley-ropeconfigurationsinanefforttoliftone-gallonwaterjugs.Theywillmeasuretheforcerequiredtoliftthewaterjugsusingspringscalesanddrawconclusionsabouttheusefulnessofeachpulley-ropeconfiguration.MaterialsØ Onesetofmaterialsforeverypairofstudents
ü 2plasticgallonsizedwaterjugs,filledü 1plasticgallonsizedwaterjug,filledhalfwayü 3nylonropes,each2meterslongü 1springscale
Procedure
1. Askstudentstobrainstormasmanywaysaspossibletomakeiteasiertoliftsomethingheavy.Generateaclasslistofideasonchartpaper.
2. Havestudentsworkwiththeirparentstoexploreavarietyofwaystouse
ropesandpulleystoliftobjects.
A. Askthentomakepredictionsaboutwhichofthefollowingconfigurationswillmakeiteasiertoliftthewaterjug.
B. Challengethemtomeasureandrecordtheforceneededtomakethe
liftineachcase.
LiftingHeavyThings,Revised2016
3. Discusswithstudentstheforcemeasurementsthattheyhavemade.
A. Askthestudentswhethertheycanexplainwhattheyhavelearned.4. Challengeyourstudentstouseadditionalmaterialsavailabletopredicthow
muchforceitwilltaketolift2gallonsofwaterineachofthesituationspicturedin#2.
A. Askthemtotesttheirpredictions.
Case1 Case2
Partner1 Partner2Partner1
Case3 Case4
Partner1
Partner1
Doorknob
LiftingHeavyThings,Revised2016
5. Askstudentstoinventwaystomakeiteasiertoliftheavyobjectsusingropesandpulleys.Encouragethemtorecordthevarietyofmethodsthattheytryalongwiththeevidencethattheyhavegathered.
JournalQuestionØ Whataresomewaysthatwillmakeiteveneasiertoliftheavythings?6. Havestudentsdrawtheconfigurationofropesandpulleystheyfeelmakesit
easiesttoliftthewaterjugs.Askthemtoincludetheevidencethattheyhaveforthisconclusion.
