parallel axis theorem

《parallel axis theorem》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、Lab.3RotationalMotionMostfundamentalconceptsaresubstractedfromthewebsite:http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.htmlCircularMotionhttp://hyperphysics.phy-astr.gsu.edu/hbase/circ.html#rotconForcircularmotionataconstantspeedv,thecentripetalaccelera

2、tionofthemotioncanbederived.Sinceinradianmeasure,c2c9ace85f3fd3d1b3e51bc749990405.doc,Page20of20BasicRotationalQuantitiesInadditiontoanytangentialacceleration,thereisalwaysthecentripetalacceleration:Theangulardisplancmentisdefinedby:Foracircularpathitfollow

3、sthattheangularvelocityisandtheangularaccelerationiswheretheaccelerationhereisthetangentialacceleration.Thestandardangleofadirectedquantityistakentobecounterclockwisefromthepositivexaxis.Torquehttp://hyperphysics.phy-astr.gsu.edu/hbase/torq.html#torqAtorque

4、isaninfluencewhichtendstochangetherotationalmotionofanobject.OnewaytoquantifyatorqueisTorque=ForceappliedxleverarmTheleverarmisdefinedastheperpendiculardistancefromtheaxisofrotationtothelineofactionoftheforce.c2c9ace85f3fd3d1b3e51bc749990405.doc,Page20of20R

5、ightHandRuleforTorqueTorqueisinherentlyavectorquantity.Partofthetorquecalculationisthedeterminationofdirection.Thedirectionisperpendiculartoboththeradiusfromtheaxisandtotheforce.Itisconventionaltochooseitintherighthandruledirectionalongtheaxisofrotation.The

6、torqueisinthedirectionoftheangularvelocitywhichwouldbeproducedbyitintheabsenceofotherinfluences.Ingeneral,thechangeinangularvelocityisinthedirectionofthetorque.Newton'sSecondLawNewton'sSecondLawasstatedbelowappliestoawiderangeofphysicalphenomena,butitisnota

7、fundamentalprincipleliketheConservationLaws.Itisapplicableonlyiftheforceisthenetexternalforce.Itdoesnotapplydirectlytosituationswherethemassischanging,eitherfromlossorgainofmaterial,orbecausetheobjectistravelingclosetothespeedoflightwhererelativisticc2c9ace

8、85f3fd3d1b3e51bc749990405.doc,Page20of20effectsmustbeincluded.Itdoesnotapplydirectlyontheverysmallscaleoftheatomwherequantummechanicsmustbeused.Datacanbeenteredintoanyoftheboxesbelow.Specifyinganytwoof