时差N小时 隧道里没信号怎么办?(下)

They generally go from eighty-eight to one-hundred-and-eight megahertz.

通常会从88到108兆赫。

That's over a hundred million cycles per second.

超过每秒一亿次。

Wow! That's pretty fast.

哇!那可是相当快。

As a result, a single radio wave from an FM station is only a few meters long, about the size of a car.

结果，FM电台单一的无线电波只有几米长,约相当于一辆车。

An AM station is putting out radio waves that are hundreds of times as long!

而AM电台伸展数百倍长的无线电波!

So the longer wavelengths¹ can't make it as easily into tunnels?

那长的电波不是更容易进入隧道吗?

Long wavelengths tend to be absorbed or blocked as they try to enter the smaller tunnel.

长电波在试图进入较小的隧道时往往被吸收或阻碍。

The higher-energy and shorter-wavelength waves from an FM station aren't absorbed or blocked as much.

而FM电台的高能量和短波长电波没有被吸收或阻碍。

Instead, they tend to bounce² around and get reflected off of surfaces.

相反,它们被从表面反弹和反射。

Like the inside of a tunnel.

像是隧道里。

Yep. Of course, they only bounce so far.

是的。当然,它们只是反弹到这段。

If the tunnel is long enough, even FM stations fade out until you come out the other end.

如果隧道足够长,甚至直到你从隧道另一端出来FM电台也会渐渐弱化。

Here we are!

我们现在就出来了!

1 wavelengths   

n.波长( wavelength的名词复数 )；具有相同的/不同的思路；合拍；不合拍

参考例句：

• I find him difficult to talk to—we're on completely different wavelengths. 我没法和他谈话，因为我们俩完全不对路。 来自《简明英汉词典》
• Sunlight consists of different wavelengths of radiation. 阳光由几种不同波长的射线组成。 来自辞典例句

2 bounce   

n.弹，反弹；冲劲，冲力；v.(使)弹起(跳起)

参考例句：

• She's got a lot of bounce.她浑身都是劲。
• The ball gave a high bounce.那球弹得很高。