<?xml version="1.0" encoding="ISO-8859-1"?><article xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
<front>
<journal-meta>
<journal-id>1870-3542</journal-id>
<journal-title><![CDATA[Revista mexicana de física E]]></journal-title>
<abbrev-journal-title><![CDATA[Rev. mex. fís. E]]></abbrev-journal-title>
<issn>1870-3542</issn>
<publisher>
<publisher-name><![CDATA[Sociedad Mexicana de Física]]></publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id>S1870-35422008000100009</article-id>
<title-group>
<article-title xml:lang="es"><![CDATA[Colisión en dirección vertical]]></article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<name>
<surname><![CDATA[Manzur]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
<xref ref-type="aff" rid="A01"/>
</contrib>
</contrib-group>
<aff id="A01">
<institution><![CDATA[,Universidad Autónoma Metropolitana Departamento de Física ]]></institution>
<addr-line><![CDATA[México D.F]]></addr-line>
<country>México</country>
</aff>
<pub-date pub-type="pub">
<day>00</day>
<month>06</month>
<year>2008</year>
</pub-date>
<pub-date pub-type="epub">
<day>00</day>
<month>06</month>
<year>2008</year>
</pub-date>
<volume>54</volume>
<numero>1</numero>
<fpage>55</fpage>
<lpage>58</lpage>
<copyright-statement/>
<copyright-year/>
<self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_arttext&amp;pid=S1870-35422008000100009&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_abstract&amp;pid=S1870-35422008000100009&amp;lng=en&amp;nrm=iso"></self-uri><self-uri xlink:href="http://www.scielo.org.mx/scielo.php?script=sci_pdf&amp;pid=S1870-35422008000100009&amp;lng=en&amp;nrm=iso"></self-uri><abstract abstract-type="short" xml:lang="es"><p><![CDATA[Se presenta un experimento de demostración que ilustra una situación en la que las leyes de conservación del ímpetu y de la energía mecánica no se cumplen; sin embargo, su uso permite obtener una buena descripción cualitativa del resultado. El objetivo se logra al analizar la colisión vertical que se produce entre dos pelotas. Las pelotas con masas apropiadas se dejan caer, con la más liviana encima de la más masiva. Después de chocar con el suelo, la pelota inferior carece de movimiento vertical, mientras que la pelota de encima rebota hasta una altura mayor que la altura desde donde fueron soltadas]]></p></abstract>
<abstract abstract-type="short" xml:lang="en"><p><![CDATA[The demonstration experiment here presented illustrates a situation where the conservation laws of linear momentum and mechanical energy are not satisfied; however, their use allows a good qualitative description of the result observed. The objective is satisfactorily gotten by the analysis of the vertical collision between two balls. The balls with the appropriate masses are dropped, the small mass resting on top of the larger mass; after the collision between the bottom ball and the floor this ball does not have vertical motion, whereas the top ball rebounds up to a height higher than its original height]]></p></abstract>
<kwd-group>
<kwd lng="es"><![CDATA[Experimentos de demostración]]></kwd>
<kwd lng="es"><![CDATA[métodos de enseñanza]]></kwd>
<kwd lng="es"><![CDATA[colisiones verticales]]></kwd>
<kwd lng="en"><![CDATA[Demonstration experiments]]></kwd>
<kwd lng="en"><![CDATA[teaching methods]]></kwd>
<kwd lng="en"><![CDATA[vertical collisions]]></kwd>
</kwd-group>
</article-meta>
</front><body><![CDATA[ <p align="justify"><font face="verdana" size="4">Ense&ntilde;anza</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="4"><b>Colisi&oacute;n en direcci&oacute;n vertical</b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="center"><font face="verdana" size="2"><b>A. Manzur</b></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><i>Departamento de F&iacute;sica, Universidad Aut&oacute;noma Metropolitana&#150;Iztapalapa, Apartado Postal 55&#150;534, 09340 M&eacute;xico, D.F., M&eacute;xico, </i>e&#150;mail: <a href="mailto:amg@xanum.uam.mx">amg@xanum.uam.mx</a></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">Recibido el 2 de agosto de 2007    <br> Aceptado el 8 de octubre de 2007</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Resumen</b></font></p>     <p align="justify"><font face="verdana" size="2">Se presenta un experimento de demostraci&oacute;n que ilustra una situaci&oacute;n en la que las leyes de conservaci&oacute;n del &iacute;mpetu y de la energ&iacute;a mec&aacute;nica no se cumplen; sin embargo, su uso permite obtener una buena descripci&oacute;n cualitativa del resultado. El objetivo se logra al analizar la colisi&oacute;n vertical que se produce entre dos pelotas. Las pelotas con masas apropiadas se dejan caer, con la m&aacute;s liviana encima de la m&aacute;s masiva. Despu&eacute;s de chocar con el suelo, la pelota inferior carece de movimiento vertical, mientras que la pelota de encima rebota hasta una altura mayor que la altura desde donde fueron soltadas.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Descriptores: </b>Experimentos de demostraci&oacute;n; m&eacute;todos de ense&ntilde;anza; colisiones verticales.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Abstract</b></font></p>     <p align="justify"><font face="verdana" size="2">The demonstration experiment here presented illustrates a situation where the conservation laws of linear momentum and mechanical energy are not satisfied; however, their use allows a good qualitative description of the result observed. The objective is satisfactorily gotten by the analysis of the vertical collision between two balls. The balls with the appropriate masses are dropped, the small mass resting on top of the larger mass; after the collision between the bottom ball and the floor this ball does not have vertical motion, whereas the top ball rebounds up to a height higher than its original height.</font></p>     <p align="justify"><font face="verdana" size="2"><b>Keywords: </b>Demonstration experiments; teaching methods; vertical collisions.</font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2">PACS:01.50.My;01.40.gb</font></p>     ]]></body>
<body><![CDATA[<p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><a href="/pdf/rmfe/v54n1/v54n1a9.pdf" target="_blank">DESCARGAR ART&Iacute;CULO EN FORMATO PDF</a></font></p>     <p align="justify"><font face="verdana" size="2">&nbsp;</font></p>     <p align="justify"><font face="verdana" size="2"><b>Referencias</b></font></p>     <!-- ref --><p align="justify"><font face="verdana" size="2">1. H.F. Meiners, Ed. Physics Demonstration Experiments. Ronald (New York, 1970).</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449202&pid=S1870-3542200800010000900001&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">2. A. Manzur Guzm&aacute;n, <i>Experimentos de Demostraci&oacute;n para F&iacute;sica I y F&iacute;sica II </i>(Universidad Aut&oacute;noma Metropolitana, M&eacute;xico, 1992).</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449203&pid=S1870-3542200800010000900002&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">3. M. Alonso y E. J. Finn, <i>F&iacute;sica, Volumen I: Mec&aacute;nica </i>(Addison&#150;Wesley Iberoamericana, M&eacute;xico, 1986) Problema 9&#150;25.</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449204&pid=S1870-3542200800010000900003&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">4. P.A. Tipler, <i>F&iacute;sica, </i>Tercera edici&oacute;n (Revert&eacute;, Barcelona, 1995) Sec. 7&#150;6.</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449205&pid=S1870-3542200800010000900004&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">5. D.T. Kagan.<i> American Journal of Physics </i>(1990) <b>58</b> 151.</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449206&pid=S1870-3542200800010000900005&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">6.<i> Nueva Enciclopedia Tem&aacute;tica: el mundo del estudiante, </i>Vig&eacute;sima s&eacute;ptima edici&oacute;n. Editorial Cumbre, M&eacute;xico, 1981. Volumen 13, pagina 546.</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449207&pid=S1870-3542200800010000900006&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --><!-- ref --><p align="justify"><font face="verdana" size="2">7.&nbsp; <i>Enciclopedia Barsa de consulta f&aacute;cil, </i>Encyclopaedia Britannica Publishers, M&eacute;xico, 1980. Tomo 14, p&aacute;gina 157.</font>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;[&#160;<a href="javascript:void(0);" onclick="javascript: window.open('/scielo.php?script=sci_nlinks&ref=8449208&pid=S1870-3542200800010000900007&lng=','','width=640,height=500,resizable=yes,scrollbars=1,menubar=yes,');">Links</a>&#160;]<!-- end-ref --> ]]></body><back>
<ref-list>
<ref id="B1">
<label>1</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Meiners]]></surname>
<given-names><![CDATA[H.F]]></given-names>
</name>
</person-group>
<source><![CDATA[Physics Demonstration Experiments]]></source>
<year>1970</year>
<publisher-loc><![CDATA[New York ]]></publisher-loc>
<publisher-name><![CDATA[Ronald]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B2">
<label>2</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Manzur Guzmán]]></surname>
<given-names><![CDATA[A]]></given-names>
</name>
</person-group>
<source><![CDATA[Experimentos de Demostración para Física I y Física II]]></source>
<year>1992</year>
<publisher-name><![CDATA[Universidad Autónoma Metropolitana]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B3">
<label>3</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Alonso]]></surname>
<given-names><![CDATA[M]]></given-names>
</name>
<name>
<surname><![CDATA[Finn]]></surname>
<given-names><![CDATA[E. J]]></given-names>
</name>
</person-group>
<source><![CDATA[Física, Volumen I: Mecánica]]></source>
<year>1986</year>
<page-range>9-25</page-range><publisher-name><![CDATA[Addison-Wesley Iberoamericana]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B4">
<label>4</label><nlm-citation citation-type="book">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Tipler]]></surname>
<given-names><![CDATA[P.A]]></given-names>
</name>
</person-group>
<source><![CDATA[Física]]></source>
<year>1995</year>
<edition>Tercera</edition>
<publisher-loc><![CDATA[Barcelona ]]></publisher-loc>
<publisher-name><![CDATA[Reverté]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B5">
<label>5</label><nlm-citation citation-type="journal">
<person-group person-group-type="author">
<name>
<surname><![CDATA[Kagan]]></surname>
<given-names><![CDATA[D.T]]></given-names>
</name>
</person-group>
<source><![CDATA[American Journal of Physics]]></source>
<year>1990</year>
<numero>58</numero>
<issue>58</issue>
<page-range>151</page-range></nlm-citation>
</ref>
<ref id="B6">
<label>6</label><nlm-citation citation-type="book">
<source><![CDATA[Nueva Enciclopedia Temática: el mundo del estudiante]]></source>
<year>1981</year>
<volume>13</volume>
<edition>séptima</edition>
<page-range>546</page-range><publisher-name><![CDATA[Editorial Cumbre]]></publisher-name>
</nlm-citation>
</ref>
<ref id="B7">
<label>7</label><nlm-citation citation-type="book">
<source><![CDATA[Enciclopedia Barsa de consulta fácil]]></source>
<year>1980</year>
<page-range>157</page-range><publisher-name><![CDATA[Encyclopaedia Britannica Publishers]]></publisher-name>
</nlm-citation>
</ref>
</ref-list>
</back>
</article>
