{"id":4700,"date":"2025-04-23T11:59:42","date_gmt":"2025-04-23T06:29:42","guid":{"rendered":"https:\/\/study.madeeasy.in\/?p=4700"},"modified":"2025-07-22T14:54:11","modified_gmt":"2025-07-22T09:24:11","slug":"energy","status":"publish","type":"post","link":"https:\/\/www.madeeasy.in\/study\/me\/engineering-mechanics\/energy","title":{"rendered":"Energy"},"content":{"rendered":"<p style=\"text-align: justify;\">Energy of a body is the capacity of to do the work. We always say, a healthy man has high capacity for doing work. A machine having higher amount of energy can perform more work.<\/p>\n<p style=\"text-align: justify;\">The unit of energy is same as work and that is Nm or Joule.<\/p>\n<h2 style=\"text-align: justify;\">Potential Energy<\/h2>\n<p style=\"text-align: justify;\">The energy possessed by an object because of its position is called <a href=\"https:\/\/study.madeeasy.in\/me\/fluid-mechanics-me\/velocity-potential-function\/\" target=\"_blank\" rel=\"noopener\">Potential Energy<\/a>. If a block of mass m is lifted through a height h above ground, then the work done on the block is mgh. The work remains stored in the block. It can perform the same amount of work again in coming down to its original position. The potential energy of mass m lifted through a height h above the ground is given by<\/p>\n<p style=\"text-align: center;\">P.E.=mgh (Nm)<\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_79_1 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-light-blue ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.madeeasy.in\/study\/me\/engineering-mechanics\/energy\/#Kinetic-Energy\" >Kinetic Energy<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.madeeasy.in\/study\/me\/engineering-mechanics\/energy\/#Spring-Energy\" >Spring Energy<\/a><\/li><\/ul><\/nav><\/div>\n<h3 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Kinetic-Energy\"><\/span>Kinetic Energy<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">The amount of work required to bring a moving body to rest is known as kinetic energy.<br \/>\nA body of mass m moving with a velocity v and is brought to rest by applying a force F, which causes retardation \u2018a\u2019 and stops the mass in the distance \u2018s\u2019, then<\/p>\n<p style=\"text-align: justify;\">Kinetic energy of the body=work used to stop the body<\/p>\n<p style=\"text-align: center;\">K.E.=F \u00b7 s = ma \u00b7 s &#8230; (i)<\/p>\n<p style=\"text-align: center;\">In this equation, we have assumed that F is constant.<br \/>\nFrom third equation of motion, we can write<\/p>\n<p style=\"text-align: center;\">0=v2 \u2013 2as<\/p>\n<p style=\"text-align: center;\">Substituting this in equation (i), we get<\/p>\n<p style=\"text-align: center;\">K.E.= 1\/2 mv2<\/p>\n<h3 style=\"text-align: justify;\"><span class=\"ez-toc-section\" id=\"Spring-Energy\"><\/span>Spring Energy<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p style=\"text-align: justify;\">Spring also stores work in the form of potential energy and is also known as spring energy.<\/p>\n<p style=\"text-align: justify;\">Consider a mass connected to a spring. At equilibrium position x = 0. Now the spring is stretched by a distance x. A force F acts on the mass due to the stiffness k of the spring that will try to bring the spring to its original position. This force is equal to<\/p>\n<p style=\"text-align: center;\">Fs=\u2013kx<\/p>\n<p style=\"text-align: justify;\"><img loading=\"lazy\" decoding=\"async\" class=\"size-full wp-image-4701 aligncenter\" src=\"https:\/\/study.madeeasy.in\/wp-content\/uploads\/2025\/04\/spring-energy.jpg\" alt=\" Spring Energy\" width=\"167\" height=\"63\" \/><\/p>\n<p style=\"text-align: justify;\">The negative sign shows that this force is always in the opposite direction of the displacement. Now consider a small displacement dx is given to mass m. Work done to stretch spring by dx is<\/p>\n<p style=\"text-align: center;\">dU=\u2013Fs dx<\/p>\n<p style=\"text-align: center;\">or dU=\u2013 (\u2013kx) dx<\/p>\n<p style=\"text-align: justify;\">\n","protected":false},"excerpt":{"rendered":"<p>Energy of a body is the capacity of to do the work. We always say, a healthy man has high<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1404,10],"tags":[1260,1405,1406],"class_list":["post-4700","post","type-post","status-publish","format-standard","hentry","category-engineering-mechanics","category-me","tag-kinetic-energy","tag-potential-energy","tag-spring-energy"],"_links":{"self":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts\/4700","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/comments?post=4700"}],"version-history":[{"count":0,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/posts\/4700\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/media?parent=4700"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/categories?post=4700"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.madeeasy.in\/study\/wp-json\/wp\/v2\/tags?post=4700"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}