科学与数学amasci.com
3M 工厂里看不见的静电墙（1996）
Invisible Electrostatic Wall at 3M plant (1996)
2011 — 2025，它一次次回到首页
黑点是上首页（≥ 50 分）的那次投稿，空心点是没冲上去的投稿，点越大分数越高。
导读
这篇页面记录了1996年流传的一个工厂见闻：在3M工厂的薄膜收卷区域，人员会感到一堵看不见的“静电墙”，靠近时像被同种电荷排斥，甚至被“钉”在地面。文中和评论尝试用塑料薄膜积累到接近理论电荷密度上限、人体带电以及地面绝缘/湿度等条件来解释，但没有给出确证。
为什么经久不衰：它把日常工业静电放大成一种反直觉的身体体验，解释又涉及电荷密度、接地与湿度，至今仍能激发讨论和复现兴趣。
HN 评论精选
同极性电荷排斥可解释“墙”感，并指出湿度、接地和放电风险。
我们大学物理课做过这个实验。只要电荷足够，同种电荷会互相排斥。我推测人身上的电荷和收卷区域产生的电荷同极性（毕竟那本质上像一台巨大的范德格拉夫起电机）。这也与湿度因素相关：潮湿空气的介电效应较弱，电荷会泄漏到周围环境，因此最大带电量更低。电场边缘给人的感觉，就像试图把同极磁铁推入磁场一样。按这里其他评论的说法，最大风险无疑是给电荷提供一条耗散的通路；在那种电量水平下，空气会被电离并产生闪电。能拍到工厂装置的照片就好了，我打赌可以追踪到电荷来源。物理101课上我们算过，人体需要多少电荷才能悬浮离地；答案比想象中小得多，难点当然是把电荷留在身上、又不偶尔电离放电电到附近东西。我一度忙着构思高介电常数衣物的概念来解决这个问题，但可惜没什么结果。
ChuckMcM查看英文原文
We did this experiment in physics back in college. If you get sufficient charge you repelled by charge of the same polarity. I would speculate that the charge on people was the same as the charge being created in the spooling area (it is a giant Van DeGraff generator type apparatus after all). That would also correlate with the humidity component as the humid air would have a lower dielectric effect and you would get a lower max charge due to leakage into the surrounding environment. The edge of that electric field would feel to you exactly like you were a magnet of the same pole trying to move into it. Per some other comments here the biggest risk would no doubt be creating a conductive path for the charge to dissipate. At those levels it can and does ionize air and create lightning. Would be great to get a picture of the factory setup. I bet you could trace the charge sources. In physics 101 we had to compute how much charge you would have to have on your body to levitate off the ground. It was a lot less then you might imagine, the challenge of course was keeping it on your body and not zapping things nearby in the occasional ionizing discharge. I was busily thinking up high K clothing concepts for a while to try to solve that issue but alas, nothing came of it.
提出薄膜接近电荷密度上限、人体与地面电阻恰好的解释，绝缘避免放电而表现为被钉住。
David Swenson 还有更多说明。关键引文：我认为最好的解释是，薄膜处于或非常接近理论电荷密度极限，且人体与地面之间的电阻恰好合适。薄膜形成的“帐篷”中心电场最强，导电的人体靠近中心时实际上被钉在地面上。如果地面更导电，人会更接近地，可能因传播型刷形放电遭到强烈电击；但由于人与地绝缘，没有发生电荷分离，于是产生了静电“钉住”效应。
yread查看英文原文
There is some more info from David Swenson: http://boards.straightdope.com/sdmb/showpost.php?s=b06561cd9b21d94322e22d4b0705566f&p=4212704&postcount=22 key quote: > I think the best explanation has to do with the film being at or vaery near the theoretical charge density limit and just the right combination of resistance between the person and floor. With the electric field at its maximum at the center of the tent formed by the film, the conductive body (person) approaching the center was actually pinned to the floor. Had the floor been more conductive, the person would have been closer to ground and probably would have received a massive shock from a propagating brush discharge. But being isolated from ground, no charge separation occured resulting in the electrostatic "pinning" effect.
认为陈旧讨论且缺乏后续验证，可信度存疑。
这是15年前的讨论了，可惜。这很可能说明它没能经受住检验。
seats查看英文原文
15 year old discussion, unfortunately. Makes it pretty likely this didn't stand up to scrutiny.
历次讨论
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