The Physical Worls: Describing Motion最新文献

Periodic motion 周期运动

The Physical Worls: Describing Motion Pub Date : 2019-05-08 DOI: 10.1201/9780429187773-4

Robert Lamboume, Alan Durrani

{"title":"Periodic motion","authors":"Robert Lamboume, Alan Durrani","doi":"10.1201/9780429187773-4","DOIUrl":"https://doi.org/10.1201/9780429187773-4","url":null,"abstract":"The ability to accurately measure time has produced many technological breakthroughs. In the seventeenth century, the inability to measure time accurately led to major navigational problems for ships crossing the Atlantic Ocean coming to America. In this century, the ability to measure time very accurately, through the use of atomic clocks, has allowed for such technological marvels as the GPS (Global Positioning System) satellite network. All devices that measure time rely on systems that undergo periodic motion. Periodic motion describes the motion of a pendulum (or a mass/spring system) that is displaced from equilibrium. Here equilibrium is the position of the pendulum bob at steady state. In order for the motion of an oscillating object to be periodic, a restoring force, must be present. A restoring force acts to bring an oscillating object back to its equilibrium position. For a pendulum, the restoring force is a portion of the gravitational pull of the earth on the pendulum bob. For a mass/spring system, the restoring force is provided by the spring’s resistance to stretch or compress. For a mass spring system the restoring force is governed by Hooke’s Law. The mathematical expression, Fspring = −k∆x (1)","PeriodicalId":307709,"journal":{"name":"The Physical Worls: Describing Motion","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-05-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120917121","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}