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They generally go from eighty-eight to one-hundred-and-eight megahertz.
通常會從88到108兆赫。
That's over a hundred million cycles per second.
超過每秒一億次。
Wow! That's pretty fast.
哇!那可是相當快。
As a result, a single radio wave from an FM station is only a few meters long, about the size of a car.
結果，FM電臺單一的無線電波只有幾米長,約相當于一輛車。
An AM station is putting out radio waves that are hundreds of times as long!
而AM電臺伸展數百倍長的無線電波!
So the longer wavelengths can't make it as easily into tunnels?
那長的電波不是更容易進入隧道嗎?
Long wavelengths tend to be absorbed or blocked as they try to enter the smaller tunnel.
長電波在試圖進入較小的隧道時往往被吸收或阻礙。
The higher-energy and shorter-wavelength waves from an FM station aren't absorbed or blocked as much.
而FM電臺的高能量和短波長電波沒有被吸收或阻礙。
Instead, they tend to bounce around and get reflected off of surfaces.
相反,它們被從表面反彈和反射。
Like the inside of a tunnel.
像是隧道里。
Yep. Of course, they only bounce so far.
是的。當然,它們只是反彈到這段。
If the tunnel is long enough, even FM stations fade out until you come out the other end.
如果隧道足夠長,甚至直到你從隧道另一端出來FM電臺也會漸漸弱化。
Here we are!
我們現在就出來了!
譯文來自網絡
