物理学史上最美的十个实验第十名Foucault'spendulum傅科钟摆实验In2001,whenscientistsmountedapendulumabovetheSouthPoleandwatcheditswing,theywerereplicatingacelebrateddemonstrationperformedinParisin1851.Usingasteelwire220feetlong,theFrenchscientistJean-Bernard-LéonFoucaultsuspendeda62-poundironballfromthedomeofthePanthéonandsetitinmotion,rockingbackandforth.Tomarkitsprogressheattachedastylustotheballandplacedaringofdampsandonthefloorbelow.Theaudiencewatchedinaweasthependuluminexplicablyappearedtorotate,leavingaslightlydifferenttracewitheachswing.ActuallyitwasthefloorofthePanthéonthatwasslowlymoving,andFoucaulthadshown,moreconvincinglythanever,thattheearthrevolvesonitsaxis.AtthelatitudeofParis,thependulum'spathwouldcompleteafullclockwiserotationevery30hours;ontheSouthernHemisphereitwouldrotatecounterclockwise,andontheEquatoritwouldn'trevolveatall.AttheSouthPole,asthemodern-dayscientistsconfirmed,theperiodofrotationis24hours.2001年,科学家们在南极安置一个摆钟,并观察它的摆动。他们是在重复1851年巴黎的一个著名实验.1851年法国科学家傅科在公众面前做了一个实验,用一根长220英尺的钢丝将一个62磅重的头上带有铁笔的铁球悬挂在屋顶下,观测记录它前后摆动的轨迹。周围观众发现钟摆每次摆动都会稍稍偏离原轨迹并发生旋转时,无不惊讶。实际上这是因为房屋在缓缓移动。傅科的演示说明地球是在围绕地轴自转的。在巴黎的纬度上,钟摆的轨迹是顺时针方向,30小时一周期。在南半球,钟摆应是逆时针转动,而在赤道上将不会转动。在南极,转动周期是24小时。