{"id":6450,"date":"1824-06-26T11:34:21","date_gmt":"1824-06-26T10:36:37","guid":{"rendered":"https:\/\/www.zsvltava.cz\/fyzika\/?p=6450"},"modified":"2026-01-27T11:38:53","modified_gmt":"2026-01-27T10:38:53","slug":"william-thomson-lord-kelvin","status":"publish","type":"post","link":"https:\/\/www.zsvltava.cz\/fyzika\/?p=6450","title":{"rendered":"William Thomson (Lord Kelvin)"},"content":{"rendered":"

William Thomson, pozd\u011bji zn\u00e1m\u00fd jako Lord Kelvin, se narodil 26. \u010dervna 1824 v Belfastu a zem\u0159el 17. prosince 1907 v Largs ve Skotsku. Byl britsk\u00fd fyzik, matematik a in\u017een\u00fdr, jedna z nejv\u00fdznamn\u011bj\u0161\u00edch osobnost\u00ed fyziky 19. stolet\u00ed. Jeho pr\u00e1ce z\u00e1sadn\u011b ovlivnila termodynamiku, elekt\u0159inu, magnetismus i in\u017een\u00fdrsk\u00e9 aplikace.<\/strong><\/p>\n

Od ml\u00e1d\u00ed byl pova\u017eov\u00e1n za v\u00fdjime\u010dn\u00fd talent. Ji\u017e v patn\u00e1cti letech nastoupil na University of Glasgow, kde se pozd\u011bji stal profesorem a p\u016fsobil zde v\u00edce ne\u017e pades\u00e1t let.<\/p>\n

Absolutn\u00ed teplotn\u00ed stupnice<\/h2>\n

Motivace a vznik Kelvinovy stupnice<\/h3>\n

Kelvin byl hluboce ovlivn\u011bn pracemi Sadiho Carnota a \u00c9mila Clapeyrona. Uv\u011bdomil si, \u017ee \u00fa\u010dinnost tepeln\u00e9ho stroje mus\u00ed souviset s teplotou definovanou nez\u00e1visle na vlastnostech l\u00e1tky. V roce 1848 proto navrhl absolutn\u00ed teplotn\u00ed stupnici, dnes zn\u00e1mou jako Kelvinova stupnice.<\/p>\n

Na t\u00e9to stupnici:<\/p>\n

– nulov\u00e1 teplota (0 K) odpov\u00edd\u00e1 stavu, kdy by ji\u017e nebylo mo\u017en\u00e9 odebrat syst\u00e9mu \u017e\u00e1dnou tepelnou energii
\n– velikost stupn\u011b je shodn\u00e1 se stupn\u011bm Celsia<\/p>\n

Kelvinova stupnice se stala z\u00e1kladn\u00edm n\u00e1strojem teoretick\u00e9 fyziky a dodnes je z\u00e1kladn\u00ed jednotkou soustavy SI.<\/p>\n

Druh\u00fd z\u00e1kon termodynamiky<\/h2>\n

Kelvin formuloval jednu z klasick\u00fdch podob druh\u00e9ho z\u00e1kona termodynamiky, zn\u00e1mou jako Kelvinovo\u2013Planckovo zn\u011bn\u00ed. Podle n\u011bj:<\/p>\n

Nen\u00ed mo\u017en\u00e9 sestrojit periodicky pracuj\u00edc\u00ed stroj, kter\u00fd by pouze odeb\u00edral teplo z jednoho z\u00e1sobn\u00edku a cel\u00e9 je p\u0159em\u011bnil na pr\u00e1ci.<\/p><\/blockquote>\n

T\u00edm jasn\u011b vymezil z\u00e1sadn\u00ed omezen\u00ed p\u0159em\u011bny tepla na pr\u00e1ci, co\u017e m\u011blo z\u00e1sadn\u00ed d\u016fsledky jak pro fyziku, tak pro technickou praxi.<\/p>\n

\u0160ir\u0161\u00ed v\u011bdeck\u00fd a technick\u00fd p\u0159\u00ednos<\/h2>\n

Kelvin se v\u00fdrazn\u011b pod\u00edlel i na praktick\u00fdch projektech:<\/p>\n

– v\u00fdvoj telegrafn\u00edch kabel\u016f, zejm\u00e9na transatlantick\u00e9ho kabelu
\n– v\u00fdzkum elektrick\u00fdch m\u011b\u0159en\u00ed a standard\u016f
\n– odhady st\u00e1\u0159\u00ed Zem\u011b na z\u00e1klad\u011b tepeln\u00e9ho chladnut\u00ed (by\u0165 pozd\u011bji korigovan\u00e9 objevem radioaktivity)<\/p>\n

Za sv\u00e9 z\u00e1sluhy byl v roce 1892 pov\u00fd\u0161en do \u0161lechtick\u00e9ho stavu a p\u0159ijal titul Lord Kelvin, odvozen\u00fd od \u0159eky Kelvin prot\u00e9kaj\u00edc\u00ed Glasgowem.<\/p>\n

V\u011bdeck\u00fd odkaz<\/h2>\n

Lord Kelvin p\u0159edstavuje spojen\u00ed hlubok\u00e9 teorie a praktick\u00e9ho in\u017een\u00fdrstv\u00ed. Spolu s Carnotem<\/a> a Clausiem<\/a> pat\u0159\u00ed k hlavn\u00edm architekt\u016fm termodynamiky a jeho pojem absolutn\u00ed teploty je dodnes nepostradateln\u00fd v cel\u00e9 fyzice.<\/p>\n","protected":false},"excerpt":{"rendered":"

William Thomson, pozd\u011bji zn\u00e1m\u00fd jako Lord Kelvin, se narodil 26. \u010dervna 1824 v Belfastu a zem\u0159el 17. prosince 1907 v Largs ve Skotsku. Byl britsk\u00fd …. <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[82],"tags":[],"class_list":["post-6450","post","type-post","status-publish","format-standard","hentry","category-osobnosti"],"_links":{"self":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/6450","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=6450"}],"version-history":[{"count":5,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/6450\/revisions"}],"predecessor-version":[{"id":6457,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/6450\/revisions\/6457"}],"wp:attachment":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=6450"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=6450"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=6450"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}