{"id":5981,"date":"2025-06-02T21:12:00","date_gmt":"2025-06-02T19:12:00","guid":{"rendered":"https:\/\/www.zsvltava.cz\/fyzika\/?p=5981"},"modified":"2025-06-03T09:39:27","modified_gmt":"2025-06-03T07:39:27","slug":"kapaliny-a-plyny-prehled","status":"publish","type":"post","link":"https:\/\/www.zsvltava.cz\/fyzika\/?p=5981","title":{"rendered":"Kapaliny a plyny &#8211; p\u0159ehled"},"content":{"rendered":"<p>Kapaliny i plyny jsou skupenstv\u00edm l\u00e1tek. Spole\u010dn\u011b je naz\u00fdv\u00e1me tekutiny. Jejich vlastnosti vych\u00e1z\u00ed z neuspo\u0159\u00e1dan\u00e9ho pohybu molekul, kter\u00e9 je tvo\u0159\u00ed. <\/p>\n<h2>Kapaliny<\/h2>\n<p>&#8211; jsou nestla\u010diteln\u00e9<br \/>\n&#8211; zauj\u00edmaj\u00ed tvar podle n\u00e1doby<br \/>\n&#8211; daj\u00ed se d\u011blit<br \/>\n&#8211; pokud jsou v klidu, je hladina vodorovn\u00e1<br \/>\n&#8211; p\u0159i ni\u017e\u0161\u00edch teplot\u00e1ch se m\u011bn\u00ed v pevn\u00e9 l\u00e1tky<br \/>\n&#8211; p\u0159i vy\u0161\u0161\u00edch teplot\u00e1ch se m\u011bn\u00ed v plyny<br \/>\n&#8211; hustota vody je p\u0159ibli\u017en\u011b 1000 kg\/m<sup>3<\/sup><\/p>\n<h3>Povrchov\u00e9 nap\u011bt\u00ed<\/h3>\n<p>Tenk\u00e1 a pru\u017en\u00e1 bl\u00e1na na povrchu umo\u017e\u0148uje dr\u017eet tvar (kapky) a tak\u00e9 zpomaluje vypa\u0159ov\u00e1n\u00ed. Je zp\u016fsobeno t\u00edm, \u017ee se u horn\u00ed vrstvy \u010d\u00e1stic neru\u0161\u00ed s\u00edly okoln\u00edch \u010d\u00e1stic.<\/p>\n<h3>Hydrostatick\u00fd tlak<\/h3>\n<p>S hloubkou roste tlak uvnit\u0159 kapaliny. Je zp\u016fsobeno t\u00edm, \u017ee p\u016fsob\u00ed svou t\u00edhou v\u00edce \u010d\u00e1stic, kter\u00e9 le\u017e\u00ed nad m\u00edstem.<\/p>\n<p><span style=\"font-size: 200%;\">p<sub>h<\/sub> = h . \u03c1 . g<\/span><\/p>\n<p>[p<sub>h<\/sub> &#8211; tlak<sub>hydrostatick\u00fd<\/sub>; h &#8211; hloubka; \u03c1 &#8211; hustota kapaliny; g &#8211; gravita\u010dn\u00ed zrychlen\u00ed]<\/p>\n<p><em>Vzore\u010dek n\u00e1m \u0159\u00edk\u00e1, \u017ee tlak je t\u00edm vy\u0161\u0161\u00ed, \u010d\u00edm vy\u0161\u0161\u00ed je hloubka a hustota kapaliny.<\/em><\/p>\n<h3>Spojen\u00e9 n\u00e1doby<\/h3>\n<p>Hladiny kapaliny ve spojen\u00e9 n\u00e1dob\u011b se ust\u00e1l\u00ed ve stejn\u00fdch v\u00fd\u0161k\u00e1ch. <\/p>\n<h3>Plav\u00e1n\u00ed t\u011bles<\/h3>\n<p>T\u011bleso se pot\u00e1p\u00ed, kdy\u017e m\u00e1 v\u011bt\u0161\u00ed hustotu ne\u017e kapalina. Pokud je hustota men\u0161\u00ed tak plave. Speci\u00e1ln\u00ed p\u0159\u00edpad nastane kdy\u017e jsou hustoty stejn\u00e9 &#8211; t\u011bleso se vzn\u00e1\u0161\u00ed.<\/p>\n<h2>Plyny<\/h2>\n<p>&#8211; vypln\u00ed v\u017edy cel\u00fd objem n\u00e1doby<br \/>\n&#8211; jsou stla\u010diteln\u00e9<br \/>\n&#8211; daj\u00ed se p\u0159el\u00e9vat stejn\u011b jako kapaliny<br \/>\n&#8211; jsou rozp\u00ednav\u00e9 &#8211; po zah\u0159\u00e1t\u00ed zv\u011bt\u0161uj\u00ed objem (pot\u0159ebuj\u00ed v\u00edce m\u00edsta)<br \/>\n&#8211; hustota vzduchu je p\u0159ibli\u017en\u011b 1 kg\/m<sup>3<\/sup><br \/>\n&#8211; plat\u00ed zde tak\u00e9 Archimed\u016fv z\u00e1kon<\/p>\n<h2>Atmosf\u00e9rick\u00fd tlak<\/h2>\n<p>Zp\u016fsobuje ho t\u00edhov\u00e1 s\u00edla vzduchu, kter\u00fd n\u00e1s obklopuje. Hodnota je p\u0159ibli\u017en\u011b 100 000 Pascal\u016f (tzv. 1 atmosf\u00e9ra). <\/p>\n<p>&#8211; P\u0159etlak &#8211; tlak m\u00e1 v\u011bt\u0161\u00ed hodnotu ne\u017e tlak atmosf\u00e9rick\u00fd.<br \/>\n&#8211; Podtlak &#8211; opak p\u0159etlaku.<\/p>\n<h2>Vakuum = vzduchopr\u00e1zdno<\/h2>\n<p>Ozna\u010den\u00ed pro \u201cpr\u00e1zdno\u201d ve kter\u00e9m nejsou ani \u010d\u00e1stice plynu. Setk\u00e1me se s n\u00edm ve voln\u00e9m prostoru vesm\u00edru. Na zemi se vytv\u00e1\u0159\u00ed um\u011ble ods\u00e1v\u00e1n\u00edm vzduchu. Nap\u0159. vakuov\u011b balen\u00e9 potraviny &#8211; odsaje se vzduch, aby se tam nemno\u017eily bakterie. (<a href=\"https:\/\/www.zsvltava.cz\/fyzika\/?p=5964\">Dozv\u011bd\u011bt se v\u00edce o vakuu.<\/a>)<\/p>\n<h2>Proud\u011bn\u00ed vzduchu<\/h2>\n<p>P\u0159\u00ed\u010dinou je rozd\u00edl tlak\u016f na 2 m\u00edstech. V r\u00e1mci spravedlivosti p\u0159\u00edrody se \u010d\u00e1stice z m\u00edsta kde je tlak v\u011bt\u0161\u00ed vydaj\u00ed do m\u00edsta kde je men\u0161\u00ed aby se tlak vyrovnal. Tento proces nikdy nekon\u010d\u00ed. Tlak se neust\u00e1le m\u011bn\u00ed v d\u016fsledku zm\u011bny teplot a vn\u011bj\u0161\u00edch vliv\u016f. \u010c\u00edm v\u011bt\u0161\u00ed je rozd\u00edl tlak\u016f, t\u00edm rychlej\u0161\u00ed a siln\u011bj\u0161\u00ed je p\u0159echod.<\/p>\n<p>&#8211; <a href=\"https:\/\/www.zsvltava.cz\/fyzika\/wp-content\/uploads\/2025\/06\/kapaliny-a-plyny-souhrn-fyzika-7r.pdf\">PDF verze pro tisk<\/a><\/p>\n<h1>10 ot\u00e1zek na prov\u011b\u0159en\u00ed znalost\u00ed<\/h1>\n<ol>\n<li>Co je to kapalina? <\/li>\n<li>Jak\u00e9 jsou z\u00e1kladn\u00ed vlastnosti kapalin?<\/li>\n<li>Co v\u00ed\u0161 o povrchov\u00e9m nap\u011bt\u00ed?<\/li>\n<li>Jak je mo\u017en\u00e9, \u017ee lo\u010f plave na hladin\u011b?<\/li>\n<li>Jak\u00e9 jsou z\u00e1kladn\u00ed vlastnosti plyn\u016f?<\/li>\n<li>Namaluj, co bychom vid\u011bli, kdybychom sledovali plyn zbl\u00edzka.<\/li>\n<li>Co je to atmosf\u00e9rick\u00fd tlak?<\/li>\n<li>Na masu je naps\u00e1no, \u017ee je vakuov\u011b baleno. Co to znamen\u00e1?<\/li>\n<li>Pro\u010d fouk\u00e1 v\u00edtr?<\/li>\n<li>Jak\u00fd panuje tlak ve vod\u011b v hloubce 64 metr\u016f?<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Kapaliny i plyny jsou skupenstv\u00edm l\u00e1tek. Spole\u010dn\u011b je naz\u00fdv\u00e1me tekutiny. Jejich vlastnosti vych\u00e1z\u00ed z neuspo\u0159\u00e1dan\u00e9ho pohybu molekul, kter\u00e9 je tvo\u0159\u00ed. Kapaliny &#8211; jsou nestla\u010diteln\u00e9 &#8211; &#8230;. <\/p>\n","protected":false},"author":1,"featured_media":5983,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[33,90],"tags":[],"class_list":["post-5981","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-7-rocnik","category-kapaliny"],"_links":{"self":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/5981","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=5981"}],"version-history":[{"count":13,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/5981\/revisions"}],"predecessor-version":[{"id":6007,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/5981\/revisions\/6007"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/media\/5983"}],"wp:attachment":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=5981"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=5981"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=5981"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}