{"id":3211,"date":"2026-10-11T17:22:39","date_gmt":"2026-10-11T04:22:39","guid":{"rendered":"https:\/\/iypt.org.nz\/?page_id=3211"},"modified":"2026-10-12T21:27:22","modified_gmt":"2026-10-12T08:27:22","slug":"problem-5-sinking-funnel","status":"publish","type":"page","link":"https:\/\/iypt.org.nz\/?page_id=3211","title":{"rendered":"Problem 5: Sinking Funnel"},"content":{"rendered":"\n<p class=\"has-text-align-center has-x-large-font-size wp-block-paragraph\">A heavy funnel bobs up and down as it sinks and sometimes tips over. Why?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">This is a deceptively simple set up with minimum construction. Have fun.<\/p>\n\n\n\n<div style=\"height:35px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Problem in full<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">This is problem 7 of 17 for IYPT 2027<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">&#8220;When a long-stemmed and sufficiently heavy funnel is released vertically into water with the stem pointing downward, it undergoes a series of damped vertical oscillations while gradually sinking. Investigate the motion and stability of the sinking funnel and the conditions under which the funnel tips over.&#8221;<\/p>\n\n\n\n<div style=\"height:35px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Specialist equipment<\/h2>\n\n\n\n<p class=\"wp-block-paragraph\">None for the experiment, but a clear sided water tank will help you film the phenomena.<\/p>\n\n\n\n<div style=\"height:35px\" aria-hidden=\"true\" class=\"wp-block-spacer\"><\/div>\n\n\n\n<h2 class=\"wp-block-heading\">Safety first!<\/h2>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Don&#8217;t leave containers of water unattended, especially if small children could reach them.<\/li>\n\n\n\n<li>Try not to spill water. It can easily spoil furnishings.<\/li>\n<\/ul>\n","protected":false},"excerpt":{"rendered":"<p>A heavy funnel bobs up and down as it sinks and sometimes tips over. Why? This is a deceptively simple set up with minimum construction. Have fun. Problem in full This is problem 7 of 17 for IYPT 2027 &#8220;When a long-stemmed and sufficiently heavy funnel is released vertically into water with the stem pointing [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":3278,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-3211","page","type-page","status-publish","has-post-thumbnail","hentry"],"_links":{"self":[{"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/pages\/3211","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/iypt.org.nz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3211"}],"version-history":[{"count":5,"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/pages\/3211\/revisions"}],"predecessor-version":[{"id":3320,"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/pages\/3211\/revisions\/3320"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/iypt.org.nz\/index.php?rest_route=\/wp\/v2\/media\/3278"}],"wp:attachment":[{"href":"https:\/\/iypt.org.nz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3211"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}