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Energy is an absolute measure of the system, whereas the force is specifically related to the set-up of the situation. </a> </div> </div> <div class="article-unit article-unit-img-wrapper group"> <div class="article-unit-img"> <a href="https://web.archive.org/web/20161118001033/http://inventors.about.com/" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.image" data-ordinal="5"> <img data-original="https://web.archive.org/web/20161118001033/http://f.tqn.com/y/inventors/1/V/-/C/1/kidoncomputer.jpg" alt="history of computers - Jason Todd/Getty Images" width="215" height="143" data-load="lazy" class=""> </a> </div> <div class="article-unit-desc"> <h5 class="heading slab-heading"> <a href="https://web.archive.org/web/20161118001033/http://inventors.about.com/" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.heading" data-ordinal="5"> World of Famous Inventors and Inventions </a> </h5> <a href="https://web.archive.org/web/20161118001033/http://inventors.about.com/" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.blurb" data-ordinal="5" class="article-blurb"> The About Inventors site has information on many inventors and inventions. An invention, of course, involves the application of physical laws to achieve a desired result. Several of the inventors profiled there have a strong background in physics. </a> </div> </div> <div class="article-unit"> <div id="afs3" class="adsense afs"></div> </div> <div class="article-unit article-unit-img-wrapper group"> <div class="article-unit-img"> <a href="https://web.archive.org/web/20161118001033/http://physics.about.com/od/lightoptics/f/Invisibility.htm" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.image" data-ordinal="6"> <img data-original="https://web.archive.org/web/20161118001033/http://f.tqn.com/y/physics/1/V/C/8/-/-/metamaterial.jpg" alt="NASA - http://www.grc.nasa.gov/WWW/RT/2003/5000/5620wilson.html" width="215" height="143" data-load="lazy" class=""> </a> </div> <div class="article-unit-desc"> <h5 class="heading slab-heading"> <a href="https://web.archive.org/web/20161118001033/http://physics.about.com/od/lightoptics/f/Invisibility.htm" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.heading" data-ordinal="6"> Is Invisibility Possible? </a> </h5> <a href="https://web.archive.org/web/20161118001033/http://physics.about.com/od/lightoptics/f/Invisibility.htm" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.blurb" data-ordinal="6" class="article-blurb"> From H.G. Wells' Invisible Man to Star Trek's cloaking devices to Harry Potter's cloak of invisibility, the prospect of turning invisible has long been a part of popular culture. Now it appears some scientists may be close to turning the dream of invisibility into a reality ... sort of. </a> </div> </div> <div class="article-unit article-unit-img-wrapper group"> <div class="article-unit-img"> <a href="https://web.archive.org/web/20161118001033/http://physics.about.com/od/physicsexperiments/" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.image" data-ordinal="7"> </a> </div> <div class="article-unit-desc"> <h5 class="heading slab-heading"> <a href="https://web.archive.org/web/20161118001033/http://physics.about.com/od/physicsexperiments/" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.heading" data-ordinal="7"> Physics Experiments </a> </h5> <a href="https://web.archive.org/web/20161118001033/http://physics.about.com/od/physicsexperiments/" data-component="categoryArticlesTemplate" data-source="ArticleSite_All" data-type="article.blurb" data-ordinal="7" class="article-blurb"> We provide you with some science experiments that students of any age can perform to help demonstrate principles of physics. Some projects are just for fun, some are "tricks," and some will allow you to obtain useful scientific data. 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