Could placing a coin on train tracks derail the train?
在铁轨上放一枚硬币会让火车脱轨吗？
原文地址：https://www.quora.com/Could-placing-a-coin-on-train-tracks-derail-the-train
Didier Szende：
Hardly…
很难。。。
This is a railway detonator. As you can see it is quite bigger than a coin. A long long time ago I worked for the French railways, and during our training, we were introduced to this device. Its purpose is to alert incoming trains that another train is stopped on the tracks. You walk — I think it was 2.2 km — upstream and downstream, and put three of those on the tracks, in a triangle, two on one rail and one on the other rail, to be sure at least one detonates. Ours were metal grey, being made of aluminium I think.
这是一个铁轨雷管。正如你所见这东西比硬币还要大一点。很久之前我曾在法国铁路工作，在我们培训期间，见识到了这个东西。设置这个东西的目的在于提醒经过的火车注意有另一辆火车停在铁轨上。你沿着在火车停止的位置上下游各大约 2.2 公里的位置以三角形的方式放置，一边铁轨放两枚，另一边放一枚来确保至少有一个能够引爆。我们的那种是银灰色的，估计是铝做的。
We had of course a couple of questions. But boss that thing is so thick, isn't it dangerous? and But boss, the noise in the engine room is so loud, surely the driver won't hear it? So the boss gave us a demo. We went to the yard, and we went first through the process of clipping it to the rail. No biggie. Then a few of us pushed a flat-bed car. It was a surprise that 8 to 10 men could push it: 1% friction will do that.
我们曾有一大堆的疑问。比如：老板，这东西太厚了，不会很危险么？老板，火车发动机的声音那么大，火车司机能听到么？然后老板给了我们一个样品。我们跑到院子里，按照第一步骤把它别到铁轨上。然后我们几个推着一辆平板挂车过去。大约 8 到 10 个人就可以推动它，事实上超过 1% 的摩擦力就可以。
And then came the bang. It still hurts my stomach thirty years later, just thinking of it. I probably lost a few % of hearing that day. Yeah. Loud enough.
然后我们听见了爆炸声。三十年后想起这个声音还让我觉得胃疼。那天我大约少了百分之几的听力。没错，那声音太大了。
