鞋帶為什麼而開 你在街上閑逛，或者者抱著一堆衣服疾馳下樓往洗衣房，俄然之間，鞋帶開了。若是你曾經經思考過，是什么讓鞋帶老是走著走著就開了，你可能須要系好鞋帶，走上通去《英國皇家學會會刊A輯》（Proceeding of the Royal Society A）的路。 在該期刊上，研究職員公布的數據註解，甩動以及踏步發生的力相結合，是鞋帶人不知;鬼不覺散開的緣故原由。 他們注重到，人們經常走著走著鞋帶就散開了，但若是是坐在桌神奇寶貝 老虎機邊晃動雙腿，或者是原地踏步不向前走，鞋帶卻不會散開。 這讓研究職員嫌疑，踏步以及擺動以某種方式配合作用，損壞了鞋帶打結的慎密度，但又是怎么做到的呢？為相識開這個“結”，研究職員拍攝了門生在跑步機上跑步的慢動作視頻，輻射4 老虎機記載下鞋帶散開的悲劇細節。 如下便是慢鏡頭望到的畫面：腳踏地發生的沖擊力會讓鞋帶中央的結變形并拉伸；在腳向吃角子老虎機前擺動時，鞋帶兩頭……[查望全文] Shoelace Study Untangles a Knotty Pro邊緣禁地 前傳 老虎機blem You’re strolling down the street or maybe hauling that load of laundry down a flight of stairs when all of a sudden. [sound fx] Your laces come undone. If you’ve ever pondered what precipitates this pedestrian wardrobe malfunction, you might want to tie your shoes and beat a path to theProceedings of the Royal Society A. In that journal, researchers have trotted out data that show that a combination of whipping and stomping forces is what causes laces to unravel without warning. The investigators noted that shoelace knots frequently fail when people are walking. But not when they are, say, sitting on the edge of a table and swinging their legs. Laces also stay tight when marching in place with no forward motion. That led the gumshoes to suspect that stepping and swinging somehow work together to foil footwear security. But how? To untangle this knotty problem, the researchers made a slo-mo video of a student running on a treadmill, thus recording the literal steps that lead to catastrophic knot failure. Here’s what they slowly saw: When the foot strikes the ground, the force of that impact causes the knot at the center of the lace to deform and stretch. And when the foot swings forward, the ends of the shoelace fly forward. That whipping motion pul角子機ls the knot open a bit more, which allows the free end of the lace…[full transcript] 訂閱最新“迷信60秒”英語消息 再也不漏失任何一次新知 plus 練耳的機遇~ 點亮贊以及在望，進修若何系緊鞋帶
2024-10-01
