{"id":7820,"date":"2012-02-11T23:50:44","date_gmt":"2012-02-11T22:50:44","guid":{"rendered":"http:\/\/volets10.fr\/WP\/?p=7820"},"modified":"2012-02-12T00:07:54","modified_gmt":"2012-02-11T23:07:54","slug":"how-wings-lift","status":"publish","type":"post","link":"https:\/\/volets10.fr\/WP\/archives\/7820\/how-wings-lift\/","title":{"rendered":"COMMENT UNE AILE CR\u00c9E LA PORTANCE ?"},"content":{"rendered":"<p><object width=\"640\" height=\"360\" classid=\"clsid:d27cdb6e-ae6d-11cf-96b8-444553540000\" codebase=\"http:\/\/download.macromedia.com\/pub\/shockwave\/cabs\/flash\/swflash.cab#version=6,0,40,0\"><param name=\"allowFullScreen\" value=\"true\" \/><param name=\"allowScriptAccess\" value=\"always\" \/><param name=\"src\" value=\"http:\/\/www.youtube.com\/v\/UqBmdZ-BNig&amp;hl=en_US&amp;feature=player_embedded&amp;version=3\" \/><param name=\"allowfullscreen\" value=\"true\" \/><param name=\"allowscriptaccess\" value=\"always\" \/><embed width=\"640\" height=\"360\" type=\"application\/x-shockwave-flash\" src=\"http:\/\/www.youtube.com\/v\/UqBmdZ-BNig&amp;hl=en_US&amp;feature=player_embedded&amp;version=3\" allowFullScreen=\"true\" allowScriptAccess=\"always\" allowfullscreen=\"true\" allowscriptaccess=\"always\" \/><\/object>On dit que la portance est obtenue par l&rsquo;air qui s&rsquo;\u00e9coule plus vite sur l&rsquo;aile que sous l&rsquo;aile \u00e0 cause de la courbature de celle-ci, car il couvre une plus longue distance. Et selon le principe de Bernoulli, si la vitesse de l&rsquo;air augmente la pression diminue\u00a0cr\u00e9ant\u00a0une force vers le haut. Que se passe-t-il alors quand un avion vole en \u00ab\u00a0verso\u00a0\u00bb ? Cette th\u00e9orie demande donc que l&rsquo;air au-dessus et au-dessous de l&rsquo;aile arrive en m\u00eame temps au bout.<\/p>\n<p>Cette vid\u00e9o d&rsquo;une minute publi\u00e9e par l&rsquo;Universit\u00e9 de Cambridge d\u00e9montre que ceci n&rsquo;est pas le cas. L&rsquo;air n&rsquo;arrive pas au bout en m\u00eame temps. La portance est donc cr\u00e9\u00e9e par la forme d&rsquo;aile uniquement.<\/p>\n<p>Lisez (en anglais) l&rsquo;article correspondant <a href=\"http:\/\/www.cam.ac.uk\/research\/news\/how-wings-really-work\/\" target=\"_blank\">ici<\/a> puis jetez un coup d&rsquo;oeuil <a href=\"http:\/\/www.espace-sciences.org\/archives\/science\/14605-comment-ca-marche-8582.html\" target=\"_blank\">ici<\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>On dit que la portance est obtenue par l&rsquo;air qui s&rsquo;\u00e9coule plus vite sur l&rsquo;aile que sous l&rsquo;aile \u00e0 cause de la courbature de celle-ci, car il couvre une plus longue distance. Et selon le principe de Bernoulli, si la vitesse de l&rsquo;air augmente la pression diminue\u00a0cr\u00e9ant\u00a0une force vers le haut. Que se passe-t-il alors [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[335],"tags":[1019,557,338,3025,984,2895,2896,983,2412,535,993],"class_list":["post-7820","post","type-post","status-publish","format-standard","hentry","category-info-technique","tag-aviation","tag-aviation-generale","tag-bernoulli","tag-info-technique","tag-la-vitesse-de-lair","tag-nouvelles","tag-nouvelles-de-laviation-generale","tag-portance","tag-volets","tag-volets10","tag-volets10-fr"],"_links":{"self":[{"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/posts\/7820"}],"collection":[{"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/comments?post=7820"}],"version-history":[{"count":0,"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/posts\/7820\/revisions"}],"wp:attachment":[{"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/media?parent=7820"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/categories?post=7820"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/volets10.fr\/WP\/wp-json\/wp\/v2\/tags?post=7820"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}