{"id":5720,"date":"2011-07-11T10:08:20","date_gmt":"2011-07-11T10:08:20","guid":{"rendered":"http:\/\/scienceblogs.com\/principles\/2011\/07\/11\/playground-physics-roller-slid\/"},"modified":"2011-07-11T10:08:20","modified_gmt":"2011-07-11T10:08:20","slug":"playground-physics-roller-slid","status":"publish","type":"post","link":"http:\/\/chadorzel.com\/principles\/2011\/07\/11\/playground-physics-roller-slid\/","title":{"rendered":"Playground Physics: Roller Slide Mystery"},"content":{"rendered":"<p>We took SteelyKid to the playground at one of the local elementary schools on Sunday morning. this one includes an odd sort of slide, made of dozens of rollers that are 1-2 inches in diameter (they&#8217;re all the same size&#8211; the range is just because I didn&#8217;t measure them carefully). They&#8217;re on really good bearings, and while it&#8217;s kind of noisy, it&#8217;s a reasonably smooth ride.<\/p>\n<p>There is, however, one slightly mysterious aspect to this slide, clearly visible in this video that Kate was good enough to shoot for me:<\/p>\n<p><iframe loading=\"lazy\" width=\"560\" height=\"349\" src=\"http:\/\/www.youtube.com\/embed\/Jf_pGMniAKA\" frameborder=\"0\" allowfullscreen><\/iframe><\/p>\n<p>SteelyKid takes something like 6 seconds to go down the slide, while it only takes me about 2 seconds to reach the bottom. This is kind of surprising, as it&#8217;s the reverse of most of the other slides we go on&#8211; usually, she handily beats me to the bottom on any set of parallel slides.<\/p>\n<p>It&#8217;s also not what you would expect for an idealized slide from introductory Newtonian physics. The acceleration of an object sliding down a ramp, even with friction, should not depend on the mass of the object. And yet, I very clearly go faster than SteelyKid does, and while I don&#8217;t have the video to test it qualitatively, I&#8217;m pretty sure Kate&#8217;s rate of sliding falls between SteelyKid and me.<\/p>\n<p>So, the question for you is: Why does that happen?<\/p>\n<p><!--more--><\/p>\n<p>After a bunch of playing around with <a href=\"http:\/\/www.cabrillo.edu\/~dbrown\/tracker\/\">Tracker Video<\/a> (I probably owe <a href=\"http:\/\/www.wired.com\/wiredscience\/dotphysics\/\">Rhett<\/a> a dollar for blog infringement), I have a possible theory, but I&#8217;m really not 100% sure what&#8217;s going on here. So I&#8217;ll throw this out to my readership: Why do I go down the roller slide so much faster than SteelyKid does, when that&#8217;s not what happens on a regular slide? Leave your theories in the comments, and I&#8217;ll post my analysis and my guess at the answer later in the week.<\/p>\n<p>(Also, the &#8220;Go, Daddy, go!&#8221; from SteelyKid after she exits the frame is totally worth uploading this to YouTube in its own right&#8230;)<\/p>\n","protected":false},"excerpt":{"rendered":"<p>We took SteelyKid to the playground at one of the local elementary schools on Sunday morning. this one includes an odd sort of slide, made of dozens of rollers that are 1-2 inches in diameter (they&#8217;re all the same size&#8211; the range is just because I didn&#8217;t measure them carefully). They&#8217;re on really good bearings,&hellip; <a class=\"more-link\" href=\"http:\/\/chadorzel.com\/principles\/2011\/07\/11\/playground-physics-roller-slid\/\">Continue reading <span class=\"screen-reader-text\">Playground Physics: Roller Slide Mystery<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"1","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[19,7,147,11,3,138,136],"tags":[],"class_list":["post-5720","post","type-post","status-publish","format-standard","hentry","category-experiment","category-physics","category-playing-with-graphs","category-science","category-steelykid","category-theory","category-video","entry"],"_links":{"self":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts\/5720","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/comments?post=5720"}],"version-history":[{"count":0,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts\/5720\/revisions"}],"wp:attachment":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/media?parent=5720"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/categories?post=5720"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/tags?post=5720"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}