{"title":"物体在无摩擦台上旋转的问题,附在悬挂物体上,用守恒定理部分求解","authors":"J. Palacios Gomez, A. S. De Ita De la Torre","doi":"10.31349/revmexfise.20.020204","DOIUrl":null,"url":null,"abstract":"Conservation theorems of Mechanics, have been applied to the problem consisting of a body rotating on a frictionless table, attached to a hanging body, as an illustrative example for students of Physics with no knowledge of sophisticated mathematical methods, how to obtain a description of the physical behavior of a system, when obtaining the equation of motion requires those complicated methods. Applying the conservation of angular momentum it is shown that the angular frequency increases inversely to the square of the radius of motion; then the radius is found at which the centripetal force and the tension of the string compensate each other; then, applying the conservation of energy, turning points are found. At the end, following scenery is obtained: the radial component of motion of the rotating body takes place between two turning points, namely a maximum at given by the initial conditions, and a minimum at . With the help of these equations, obtained without the need of solving differential equations, it is possible to obtain a semi quantitative physical behavior of this particular system.","PeriodicalId":49600,"journal":{"name":"Revista Mexicana De Fisica E","volume":" ","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2023-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"The problem of the body rotating on a frictionless table, attached to a hanging body, solved partially by conservation theorems\",\"authors\":\"J. Palacios Gomez, A. S. De Ita De la Torre\",\"doi\":\"10.31349/revmexfise.20.020204\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"Conservation theorems of Mechanics, have been applied to the problem consisting of a body rotating on a frictionless table, attached to a hanging body, as an illustrative example for students of Physics with no knowledge of sophisticated mathematical methods, how to obtain a description of the physical behavior of a system, when obtaining the equation of motion requires those complicated methods. Applying the conservation of angular momentum it is shown that the angular frequency increases inversely to the square of the radius of motion; then the radius is found at which the centripetal force and the tension of the string compensate each other; then, applying the conservation of energy, turning points are found. At the end, following scenery is obtained: the radial component of motion of the rotating body takes place between two turning points, namely a maximum at given by the initial conditions, and a minimum at . With the help of these equations, obtained without the need of solving differential equations, it is possible to obtain a semi quantitative physical behavior of this particular system.\",\"PeriodicalId\":49600,\"journal\":{\"name\":\"Revista Mexicana De Fisica E\",\"volume\":\" \",\"pages\":\"\"},\"PeriodicalIF\":0.0000,\"publicationDate\":\"2023-06-28\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Revista Mexicana De Fisica E\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.31349/revmexfise.20.020204\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q4\",\"JCRName\":\"Social Sciences\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Revista Mexicana De Fisica E","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.31349/revmexfise.20.020204","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"Social Sciences","Score":null,"Total":0}
The problem of the body rotating on a frictionless table, attached to a hanging body, solved partially by conservation theorems
Conservation theorems of Mechanics, have been applied to the problem consisting of a body rotating on a frictionless table, attached to a hanging body, as an illustrative example for students of Physics with no knowledge of sophisticated mathematical methods, how to obtain a description of the physical behavior of a system, when obtaining the equation of motion requires those complicated methods. Applying the conservation of angular momentum it is shown that the angular frequency increases inversely to the square of the radius of motion; then the radius is found at which the centripetal force and the tension of the string compensate each other; then, applying the conservation of energy, turning points are found. At the end, following scenery is obtained: the radial component of motion of the rotating body takes place between two turning points, namely a maximum at given by the initial conditions, and a minimum at . With the help of these equations, obtained without the need of solving differential equations, it is possible to obtain a semi quantitative physical behavior of this particular system.
期刊介绍:
The Revista Mexicana de Física (Rev. Mex. Fis.) publishes original papers of interest to our readers from the physical science com unity. Language may be English or Spanish, however, given the nature of our readers, English is recommended. Articles are classified as follows:
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Comments. Short papers (four pages maximum) that assess critically papers by others authors previously published in the Revista Mexicana de Física. A comment should state clearly to which paper it refers.