{"id":1254,"date":"2010-08-04T16:00:00","date_gmt":"2010-08-04T23:00:00","guid":{"rendered":"https:\/\/www.reenigne.org\/blog\/?p=1254"},"modified":"2010-08-04T09:03:26","modified_gmt":"2010-08-04T16:03:26","slug":"simple-harmonic-motion","status":"publish","type":"post","link":"https:\/\/www.reenigne.org\/blog\/simple-harmonic-motion\/","title":{"rendered":"Simple Harmonic Motion"},"content":{"rendered":"<p>Some 14 years ago when learning about second order differential equations, simulating physical systems on computers and simple harmonic motion, I wrote this DOS program which (because it&#8217;s kind of fun to play with) I have now translated into flash:<\/p>\n<p align=\"center\"><object class=\"centerwide\" width=\"400\" height=\"240\"><embed src=\"http:\/\/www.reenigne.org\/shm\/shm.swf\" type=\"application\/x-shockwave-flash\" width=\"400\" height=\"240\"><\/embed><\/object><\/p>\n<p>The idea is very simple &#8211; it&#8217;s just a mass (the white ball) with a green pen, connected to a point by a piece of elastic (the white line). The point doesn&#8217;t move except when the mouse button is held down, when it moves to the mouse pointer location. This means that the mouse is essentially the forcing function for a 2D, second-order linear differential equation. Which means that (depending on the parameters) the mass follows the mouse pointer, possibly smoothing out its motion, possibly oscillating around it.<\/p>\n<p>There are two slider controls on the right &#8211; the leftmost one (or the + and &#8211; keys) controls the tension and the rightmost one (or the < and > keys) controls the friction. Press escape to clear the screen.<\/p>\n<p><a href=\"http:\/\/www.reenigne.org\/misc\/shm.zip\">Source code.<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Some 14 years ago when learning about second order differential equations, simulating physical systems on computers and simple harmonic motion, I wrote this DOS program which (because it&#8217;s kind of fun to play with) I have now translated into flash: The idea is very simple &#8211; it&#8217;s just a mass (the white ball) with a [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[48],"tags":[],"class_list":["post-1254","post","type-post","status-publish","format-standard","hentry","category-applets"],"_links":{"self":[{"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/posts\/1254","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/comments?post=1254"}],"version-history":[{"count":3,"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/posts\/1254\/revisions"}],"predecessor-version":[{"id":1263,"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/posts\/1254\/revisions\/1263"}],"wp:attachment":[{"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/media?parent=1254"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/categories?post=1254"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.reenigne.org\/blog\/wp-json\/wp\/v2\/tags?post=1254"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}