时差N小时 锚应该抛多远？（在线收听）

Anchors away, me boys-but how far?

抛锚了，锚究竟该抛多远呢？

On this moment of science.

又到了科学一刻的时间了。

What happens if you throw your anchor overboard and there isn't enough chain to reachthe bottom?

如果你将锚抛出船外，但锚还不够长，没法触底固定，

Does the anchor haul you down with it?

那么锚会把船拖下水吗？

This sounds a little bit like something that would happen in a cartoon.

这听起来像是动画片里才能看到场景，

But for sailors it's nolaughing matter.

但对水手来说可不是开玩笑。

It's unlikely the whole ship would be pulled under, but there could very well be damage to the hull caused by not having enough chain-including a sudden hole where the anchor used to be.

发生这种情况时，整艘船被拖下水可能性不大，但船体很有可能受到大的破坏，比如船上原本固定锚的地方会被突然扯出一个洞。

That's why the nautical rule of thumb is to use three times as much chain as is needed to hit bottom.

所以，对于航海有条黄金法则：使用比触底所需的长度长两倍的锚。

That extra chain piles up around the anchor and provides added stability.

多余部分的锚链会在固定锚的周围盘起，从而加强船的稳定性。

Still, what if you don't know how deep the water is?

但要是不知道水有多深，

Or what if you just make a mistake?

或者不小心失误了怎么办？

The navy has prepared for this by building what is called a weak link into their anchor chains.

为了解决这个问题，海军设计了有弱环链接的锚链。

The weak link is the last link in the chain, and while it's strong enough to hold together in general,it's weak enough to break if the whole weight of the anchor and chain is put on it.

弱环是锚链的最后一环，通常它可以紧扣锚链，在受到整条锚链的重力时才会断裂，

The weak link there is as a safety valve.

就像一个安全阀门。

Because it's the very last link, under normal circumstances it never getsplayed out at all; you always want to have some chain left on the ship.

正因为它是整条锚链的最后一环，一般根本受不到力，因为总有一部分链条还留在船上。

But, if the anchor is still zooming down full speed at the point where the entire chain runs out, the abrupt jerk will cause that link to snap.

但要是在整条锚链已完全抛出，锚还在急速下降，猛然的拉动还是会扯断弱环。

Without the safety valve of the weak link, sailors might routinely drop more than their anchors.

如果没有弱环作为安全阀，恐怕被抛入水底的就是那些水手了。