{"id":1120,"date":"2025-03-05T10:57:06","date_gmt":"2025-03-05T09:57:06","guid":{"rendered":"http:\/\/www.zsvltava.cz\/fyzika\/?p=1120"},"modified":"2025-04-10T07:27:11","modified_gmt":"2025-04-10T05:27:11","slug":"treci-sila","status":"publish","type":"post","link":"https:\/\/www.zsvltava.cz\/fyzika\/?p=1120","title":{"rendered":"T\u0159ec\u00ed s\u00edla"},"content":{"rendered":"

T\u0159ec\u00ed s\u00edla ur\u010duje velikost vz\u00e1jemn\u00e9ho p\u016fsoben\u00ed ploch t\u011bles, kter\u00e9 se spolu dot\u00fdkaj\u00ed. Vz\u00e1jemn\u00e9 p\u016fsoben\u00ed vypl\u00fdv\u00e1 ze skute\u010dnosti, \u017ee \u017e\u00e1dn\u00e1 plocha nen\u00ed dokonale rovn\u00e1 a hladk\u00e1.<\/strong><\/p>\n

\"\"<\/p>\n

Poh\u00e1r na obr\u00e1zku se na\u0161emu oku jev\u00ed jako dokonale hladk\u00fd. Pokud bychom se pod\u00edvali speci\u00e1ln\u00edm mikroskopem, zjistili bychom, \u017ee ve skute\u010dnosti vypad\u00e1 povrch asi n\u00e1sledovn\u011b:<\/p>\n

\"\"<\/a><\/p>\n

Na obr\u00e1zku je vid\u011bt 2 mm x 2 mm zd\u00e1nliv\u011b hladk\u00e9ho poniklovan\u00e9ho povrchu v p\u0159ibl\u00ed\u017een\u00ed na n\u011bkolik mikro metr\u016f. (Tedy 10 000 x men\u0161\u00ed ne\u017e centimetr.)<\/p>\n

Ocel pod mikroskopem<\/h3>\n

\"\"<\/a><\/p>\n

Source: https:\/\/www.mccrone.com\/<\/p>\n

Smykov\u00e9 t\u0159en\u00ed<\/h2>\n

Vznik\u00e1, kdy\u017e se t\u011blesa po sob\u011b sm\u00fdkaj\u00ed. Sm\u00fdkat je synonymum ke slovu t\u00e1hnout<\/strong>.<\/p>\n

– Simulace na PHET<\/a><\/p>\n

T\u0159ec\u00ed s\u00edla Z\u00c1VIS\u00cd na:<\/h3>\n
    \n
  • druhu povrchu – materi\u00e1lu,<\/li>\n
  • hmotnosti t\u011blesa.<\/li>\n<\/ul>\n

    T\u0159ec\u00ed s\u00edla NEZ\u00c1VIS\u00cd na:<\/h3>\n
      \n
    • velikosti povrchu,<\/li>\n
    • na rychlosti pohybu. (Plat\u00ed p\u0159i b\u011b\u017en\u00fdch rychlostech a velikostech.)<\/li>\n<\/ul>\n

      Valiv\u00e9 t\u0159en\u00ed<\/h2>\n

      Vznik\u00e1 valen\u00edm koule, v\u00e1lce nebo ku\u017eele. Je v\u017edy men\u0161\u00ed ne\u017e t\u0159en\u00ed smykov\u00e9. Pou\u017e\u00edv\u00e1me tam, kde chceme aby byly t\u0159ec\u00ed (odporov\u00e9) s\u00edly co nejmen\u0161\u00ed.<\/p>\n

      Tam kde se t\u011bleso ot\u00e1\u010d\u00ed, se na m\u00edsto t\u0159ec\u00edch ploch d\u00e1v\u00e1 lo\u017eisko. To m\u00e1 za \u00fakol co nejv\u00edce zmen\u0161it t\u0159ec\u00ed plochu.<\/p>\n

      \"\"<\/p>\n

      Lo\u017eisko je z\u00e1kladem popul\u00e1rn\u00ed relaxa\u010dn\u00ed hra\u010dky.<\/p>\n

      \"\"<\/p>\n

      \n

      Image source \/ obr\u00e1zek niklov\u00e9ho povrchu poch\u00e1z\u00ed ze serveru: AZONANO.com<\/small><\/p>\n","protected":false},"excerpt":{"rendered":"

      T\u0159ec\u00ed s\u00edla ur\u010duje velikost vz\u00e1jemn\u00e9ho p\u016fsoben\u00ed ploch t\u011bles, kter\u00e9 se spolu dot\u00fdkaj\u00ed. Vz\u00e1jemn\u00e9 p\u016fsoben\u00ed vypl\u00fdv\u00e1 ze skute\u010dnosti, \u017ee \u017e\u00e1dn\u00e1 plocha nen\u00ed dokonale rovn\u00e1 a hladk\u00e1. …. <\/p>\n","protected":false},"author":1,"featured_media":1125,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[35],"tags":[15],"class_list":["post-1120","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-sila","tag-pod-mikroskopem"],"_links":{"self":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/1120","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=1120"}],"version-history":[{"count":0,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/posts\/1120\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=\/wp\/v2\/media\/1125"}],"wp:attachment":[{"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1120"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1120"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.zsvltava.cz\/fyzika\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1120"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}