钟摆的周期-Period-of-a-PendulumPPT课件

PeriodofaPendulumHypothesis…..IfthemassofthebobisincreasethentheperiodwillbelongerTheperiodofpendulumwillbeaffectedbythemassVariables….Dependentvariable:Period(time)Independentvariable:massofthebobControlledvariable:angleofdisplacement,lengthofpendulum,distribution(thesevariableswillnotbechanged)Controlledvariables….Controlledvariable.1angleofdisplacementvalue:20degreeControlledvariable.2lengthofpendulumvalue:50cmControlledvariable.3distributionvalue:attheendofthependulumDatacollectionTrial#Iv1Iv2Iv3Iv4Iv5T114.5214.0514.6514.1614.45T214.7514.0614.5214.2014.53T314.5813.9814.5914.1314.45T414.6614.0714.1714.1514.52T514.5814.3314.3914.0814.55TAve+_1.51.41.41.41.4GraphAnalysis:A.Ourindependentvariablewasthemassofthebob,wefoundthatthereisnorelationshipbetweentheperiodandthemass,wecanbeconfidentaboutitbecausetherewasnoreallybigchangeintimingduringchangingthemassB.wecanmentionthisfromthedatacollectionC.thedatacannotshowthestrongcorrelationbetweenthevariables.E.whydoyouthinkMr.Purcellgavespecificinstructionsabouthowtousethestopwatch？Thiscanbetheevidenceforwhywetimed10periodsduringapendulumexperimentratherthanonlyone,ifwemeasuremanyperiodsourerrordoesnotincrease,wecangetamoreaccurateanswerbytiming10periods.ourhypothesiswaswrong,wethoughtthatifthemassincreasethentheperiodwillbelongerbutrealdataprovedthatthereisnorelationshipbetweenthemassandtheperiod.Everymeasurementwemakehasanuncertainty…..Measurementsareneverperfect,themoremeasurementsyoutakeofthesameparameter,themoreaccuratelyyoucancalculatethevaluethelargestuncertaintyisperiod,becausewecan’tstopthestopwatchattheexactrighttimeWhat’stheuncertainty?TheimperfectioninallmeasurementsiscalleduncertaintyInthephysicswewillwriteanuncertaintyalmosteverytimewemeasureameasurement(measuredvalue+_uncertainty)properunitsWefoundouttheRelatedfactorsontheinternet.Thereisarelationshipbetweentheperiodandthelength.Accelerationofgravityalsoaffectstheperiod.PeriodofaPendulum’sformula:ThankYou!BYKatherineandVicky