{"id":1648,"date":"2022-04-26T15:08:44","date_gmt":"2022-04-26T13:08:44","guid":{"rendered":"https:\/\/mxth.dk\/?page_id=1648"},"modified":"2023-08-29T21:28:08","modified_gmt":"2023-08-29T19:28:08","slug":"bestemmelse-af-den-specifikke-varmekapacitet-for-et-lod","status":"publish","type":"page","link":"https:\/\/mxth.dk\/?page_id=1648","title":{"rendered":"Bestemmelse af den specifikke varmekapacitet for et lod"},"content":{"rendered":"\n<div class=\" wp-block-cover alignfull is-light has-parallax eplus-wrapper\"><span aria-hidden=\"true\" class=\"wp-block-cover__background has-background-dim\"><\/span><div role=\"img\" class=\"wp-block-cover__image-background wp-image-2638 has-parallax\" style=\"background-position:50% 50%;background-image:url(https:\/\/mxth.dk\/wp-content\/uploads\/2023\/08\/soroush-karimi-EtVcfGToHkQ-unsplash-scaled.jpg)\"><\/div><div class=\"wp-block-cover__inner-container is-layout-flow wp-block-cover-is-layout-flow\"><p class=\" has-text-align-center has-large-font-size eplus-wrapper eplus-styles-uid-0bc07b\">FORS\u00d8G<\/p>\n\n<p class=\" has-text-align-center eplus-wrapper eplus-styles-uid-f9d093\">bestemmelse af den spefikke varmekapacitet for et lod<\/p><\/div><\/div>\n\n\n\n<p class=\" eplus-wrapper\">Vi vil her bestemme den specifikke varmekapacitet af et lod. Til at g\u00f8re dette vil vi varme loddet op til en kendt v\u00e6rdi, herefter s\u00e6nke det ned i vand med en kendt temperatur for herefter at m\u00e5le hvilken temperatur vandet f\u00e5r n\u00e5r loddet afgiver varme til vandet. Det vil derefter v\u00e6re muligt at bestemme hvor meget varme loddet har afgivet og hvor meget varme vandet har optaget. Det vil sige, at vi kan opstille to ligninger<\/p>\n\n\n\n<p class=\" has-text-align-center eplus-wrapper\">$\\begin{align}&amp;Q_{vand}=m_{vand}\\cdot c_{vand}\\cdot \\Delta T\\\\<br>&amp;Q_{lod}=m_{lod}\\cdot c_{lod}\\cdot \\Delta T\\end{align}$<\/p>\n\n\n\n<p class=\" eplus-wrapper\">hvor $\\small \\Delta T = T_{slut}-T_{start}$.<\/p>\n\n\n\n<p class=\" eplus-wrapper\">Hvis vi antager et isoleret system s\u00e5 vil $Q_{vand}+Q_{lod}=0$, da loddet vil afgive sin varme til vandet og derved er $\\small Q_{vand}$ positiv, mend $\\small Q_{lod}$ er negativ.<\/p>\n\n\n\n<p class=\" eplus-wrapper\">Vi har derfor, at<\/p>\n\n\n\n<p class=\" eplus-wrapper\">$\\begin{equation}\\tag{*}m_{vand}\\cdot c_{vand}\\cdot (T_{slut}-T_{start, vand})+m_{lod}\\cdot c_{lod}\\cdot (T_{slut}-T_{start, lod})=0\\label{eq_all}\\end{equation}$<\/p>\n\n\n\n<p class=\" eplus-wrapper\">Vi kan m\u00e5le alle st\u00f8rrelser end $\\small c_{lod}$, hvorved vi derfor kan bestemme den.<\/p>\n\n\n\n<h5 class=\" wp-block-heading eplus-wrapper\">Materialeliste<\/h5>\n\n\n<ul class=\"eplus-wrapper wp-block-list eplus-styles-uid-757d70\">\n<li class=\" eplus-wrapper\">Elk\u00e6del<\/li>\n\n\n\n<li class=\" eplus-wrapper\">Termob\u00e6ger<\/li>\n\n\n\n<li class=\" eplus-wrapper\">Termometer<\/li>\n\n\n\n<li class=\" eplus-wrapper\">Vand<\/li>\n\n\n\n<li class=\" eplus-wrapper\">V\u00e6gt<\/li>\n\n\n\n<li class=\" eplus-wrapper\">Lod<\/li>\n<\/ul>\n\n\n<h5 class=\" wp-block-heading eplus-wrapper\">Fremgangsm\u00e5de<\/h5>\n\n\n<ol class=\"eplus-wrapper wp-block-list eplus-styles-uid-39842f\">\n<li class=\" eplus-wrapper\">m\u00e5l massen af loddet og af vandet (ekscl. termob\u00e6ger). Noter masserne ned.<\/li>\n\n\n\n<li class=\" eplus-wrapper\">kog vandet og hold loddet ned i det varme vand i 5 min (kan v\u00e6re man g\u00f8r det over flere gange &#8211; alts\u00e5 genkoger vandet &#8211; for at s\u00f8rge for at vandet er $\\small 100^\\circ C$)<\/li>\n\n\n\n<li class=\" eplus-wrapper\">m\u00e5l temperaturen af vandet i termob\u00e6geret.<\/li>\n\n\n\n<li class=\" eplus-wrapper\">overf\u00f8r hurtigt det 100 grader varme lod til vandet i termob\u00e6geret<\/li>\n\n\n\n<li class=\" eplus-wrapper\">m\u00e5l kontinuerligt temperaturen af vandet og noter temperaturen ned n\u00e5r den har opn\u00e5et en konstant v\u00e6rdi (omr\u00f8r n\u00e5r der m\u00e5les)<\/li>\n<\/ol>\n\n\n<h5 class=\" wp-block-heading eplus-wrapper\">DATA<\/h5>\n\n\n\n<p class=\" eplus-wrapper\">I skal notere forskellige st\u00f8rrelser ned s\u00e5ledes s\u00e5 I har mulighed for at beregne den specifikke varmekapacitet for loddet. Herunder ses en liste over de ting som I skal notere ned<\/p>\n\n\n\n<p class=\" eplus-wrapper\">$\\;\\;\\;m_{vand}=$<br>$\\;\\;\\;m_{lod}=$<br>$\\;\\;\\;T_{start,vand}=$<br>$\\;\\;\\;T_{start,lod}=100\\;^{\\circ}\\!C$ <a href=\"#footnote-1-1648\" id=\"note-1-1648\" rel=\"footnote\">1<\/a><br>$\\;\\;\\;T_{slut}=$<br>$\\;\\;\\;c_{vand}=4180\\frac{J}{kg\\cdot\\;^{\\circ}C}$<br>$\\;\\;\\;c_{lod}=?$<\/p>\n\n\n\n<h5 class=\" wp-block-heading eplus-wrapper\">DATABEHANDLING<\/h5>\n\n\n\n<p class=\" eplus-wrapper\">Isoler $\\small c_{lod}$ i ligning \\eqref{eq_all}.<\/p>\n\n\n\n<p class=\" eplus-wrapper\">Beregn den specifikke varmekapacitet for loddet.<\/p>\n\n\n\n<p class=\" eplus-wrapper\">Tjek resultatet ved at sl\u00e5 op i en tabel over specifikke varmekapaciteter (se bilag).<\/p>\n\n\n\n<h5 class=\" wp-block-heading eplus-wrapper\">Diskusion og vurdering<\/h5>\n\n\n\n<p class=\" eplus-wrapper\">Hvilket metal er loddet lavet af?. Passer dit opslag med det du forventede? Var der ingen metaller der passede, i s\u00e5 fald hvad var den relative afvigelse p\u00e5 det som var t\u00e6ttest p\u00e5? Hvilke \u00e5rsager kunne der v\u00e6re til denne afvigelse (fejlkilder)?<\/p>\n\n\n\n<h5 class=\" wp-block-heading eplus-wrapper\">Bilag<\/h5>\n\n\n\n<p class=\" eplus-wrapper\">Tabellen herunder indeholder v\u00e6rdier for den specifikke varmekapacitet for udvalgte materialer. Der er ogs\u00e5 to links, hvor der kan findes uderligere v\u00e6rdier.<\/p>\n\n\n\n<figure class=\" wp-block-image aligncenter size-large eplus-wrapper\"><img data-recalc-dims=\"1\" loading=\"lazy\" decoding=\"async\" width=\"523\" height=\"1024\" src=\"https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2022\/04\/0C41AB70-4380-48C9-A41D-023593BBDD62.jpeg?resize=523%2C1024&#038;ssl=1\" alt=\"\" class=\"wp-image-1657\" srcset=\"https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2022\/04\/0C41AB70-4380-48C9-A41D-023593BBDD62.jpeg?resize=523%2C1024&amp;ssl=1 523w, https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2022\/04\/0C41AB70-4380-48C9-A41D-023593BBDD62.jpeg?resize=153%2C300&amp;ssl=1 153w, https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2022\/04\/0C41AB70-4380-48C9-A41D-023593BBDD62.jpeg?resize=768%2C1504&amp;ssl=1 768w, https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2022\/04\/0C41AB70-4380-48C9-A41D-023593BBDD62.jpeg?resize=785%2C1536&amp;ssl=1 785w, https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2022\/04\/0C41AB70-4380-48C9-A41D-023593BBDD62.jpeg?w=1046&amp;ssl=1 1046w\" sizes=\"auto, (max-width: 523px) 100vw, 523px\" \/><figcaption class=\"wp-element-caption\">Tabel over specifik varmekapacitet for forskellige materialer. Taget fra Physics for Scientists and Engineers with Modern Physics, 6th Edition.<\/figcaption><\/figure>\n\n\n\n<p class=\" eplus-wrapper\">Link til Wikipedia artikel om varmekapacitet: <a href=\"https:\/\/da.wikipedia.org\/wiki\/Varmekapacitet\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/da.wikipedia.org\/wiki\/Varmekapacitet<\/a><\/p>\n\n\n\n<p class=\" eplus-wrapper\">Link til kapitlet om specifik varmekapacitet i Orbit B HTX p\u00e5 systime: <a href=\"https:\/\/orbithtxb.systime.dk\/?id=c3554&amp;L=0\" target=\"_blank\" rel=\"noreferrer noopener\">https:\/\/orbithtxb.systime.dk\/?id=c3554&amp;L=0<\/a><\/p>\n<div class=\"footnotes\"><hr \/><ol><li id=\"footnote-1-1648\" class=\"footnote\"><p>hvis man har m\u00e5lt en anden v\u00e6rdi eller antaget en anden temperatur s\u00e5 skal den selvf\u00f8lgelig rettes<a href=\"#note-1-1648\" class=\"footnote-return\">&#8617;<\/a><\/p><\/li><!--\/#footnote-1.footnote--><\/ol><\/div><!--\/#footnotes-->","protected":false},"excerpt":{"rendered":"<p>Vi vil her bestemme den specifikke varmekapacitet af et lod. Til at g\u00f8re dette vil vi varme loddet op til en kendt v\u00e6rdi, herefter s\u00e6nke det ned i vand med en kendt temperatur for herefter at m\u00e5le hvilken temperatur vandet f\u00e5r n\u00e5r loddet afgiver varme til vandet.<\/p>\n","protected":false},"author":1,"featured_media":2638,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"ub_ctt_via":"","editor_plus_copied_stylings":"{}","footnotes":""},"categories":[27,2],"tags":[],"class_list":["post-1648","page","type-page","status-publish","has-post-thumbnail","hentry","category-forsoeg","category-fysik"],"featured_image_src":"https:\/\/i0.wp.com\/mxth.dk\/wp-content\/uploads\/2023\/08\/soroush-karimi-EtVcfGToHkQ-unsplash-scaled.jpg?fit=2560%2C1707&ssl=1","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/pages\/1648","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mxth.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1648"}],"version-history":[{"count":35,"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/pages\/1648\/revisions"}],"predecessor-version":[{"id":2643,"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/pages\/1648\/revisions\/2643"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/mxth.dk\/index.php?rest_route=\/wp\/v2\/media\/2638"}],"wp:attachment":[{"href":"https:\/\/mxth.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1648"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mxth.dk\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1648"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mxth.dk\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1648"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}