{"id":427790,"date":"2017-06-29T02:00:00","date_gmt":"2017-06-28T23:00:00","guid":{"rendered":"https:\/\/www.fyysika.ee\/?guid=cbb1af87cbbdf91948c3456eb4f2ea49"},"modified":"2017-06-29T02:00:00","modified_gmt":"2017-06-28T23:00:00","slug":"origins-of-rolling-friction-2","status":"publish","type":"post","link":"https:\/\/www.fyysika.ee\/?p=427790","title":{"rendered":"Origins of rolling friction"},"content":{"rendered":"<p>When a hard object rolls on a soft surface, or vice versa, rolling friction arises from deformation<br \/>\nof the soft object or the soft surface. The friction force can be described in terms of an offset in<br \/>\nthe normal reaction force or in terms of energy loss arising from the deformation. The origin of the<br \/>\nfriction force itself is not entirely clear. It is investigated qualitatively in this paper by<br \/>\nrolling a steel ball on soft foam and by rolling a foam cylinder on a hard surface. The deformation<br \/>\nof the foam was observed visually, providing simple insights into the origin of the friction force.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>When a hard object rolls on a soft surface, or vice versa, rolling friction arises from deformation<br \/>\nof the soft object or the soft surface. The friction force can be described in terms of an offset in<br \/>\nthe normal reaction force or in terms of energy l&#8230;<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","footnotes":""},"categories":[178],"tags":[],"class_list":{"0":"post-427790","1":"post","2":"type-post","3":"status-publish","4":"format-standard","6":"category-rss-fuusikaharidus","7":"entry"},"_links":{"self":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/427790","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=427790"}],"version-history":[{"count":0,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=\/wp\/v2\/posts\/427790\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=427790"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=427790"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.fyysika.ee\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=427790"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}