《那些古怪又讓人憂心的問題》第81期:飛越減速帶(3)
While most passenger cars have some kind ofartificial speed limits imposed by the engine computer, the ultimate physicallimit to a car's top speed comes from air resistance. This type of dragincreases with the square of speed; at some point, a car doesn't have enoughengine power to push through the air any faster.
雖然絕大部分轎車的發動機控制器都會有意限制最高速度，但汽車最高時速的終極物理限制在於空氣阻力。這種阻力與速度的平方成正比，在某個速度下，再怎麼踩油門汽車也不會再加速了。
If you did force a sedan to go faster thanits top speed-perhaps by reusing the magical accelerator from the relativisticbaseball-the speed bump would be the least of your problems.
但如果你真的迫使一輛小轎車——比如通過使用光速棒球中出現的魔力加速器——以高於其最高時速的速度行駛，那麼減速帶會是你所有問題裏最不重要的一個。
Cars generate lift. The air flowing arounda car exerts all kinds of forces on it.
因爲汽車會產生升力，流經汽車表面的空氣會對其施加各種各樣的力。
Where did all these arrows come from?
這些箭頭是從哪兒來的？
The lift forces are relatively minor atnormal highway speeds, but at higher speeds they become substantial.
在普通的高速公路時速下，升力相對來說微不足道，但在極高的速度下它們就會產生非常大的影響。
In a Formula One car equipped withairfoils, this force pushes downward, holding the car against the track. In asedan, they lift it up.
在裝有擾流板的F1賽車上，這股力將賽車往賽道上壓，使賽車保持在賽道上。而在普通的轎車上，這股力會將汽車擡起來。
Among NASCAR fans, there's frequently talkof a 200-mph “liftoff speed”if the car starts to spin. Other branches of auto racing have seenspectacular backflip crashes when the aerodynamics don't work out as planned.
在全國運動汽車競賽協會，每小時200英里（約322千米）被普遍認爲是汽車的“起飛速度”——此時車會開始旋轉。在其他種類的賽車比賽中，我們看到過壯觀的後空翻式車禍，這就是汽車的空氣動力學特性並沒有像預想的那樣發揮作用的後果。
The bottom line is that in the range of 150–300 mph, a typical sedan would lift off the ground, tumble, andcrash . . . before you even hit the bump.
我覺得最低在每小時150英里（約241千米）到300英里（約483千米）這個區間內，一輛普通的小轎車就會騰空而起，華麗麗地開始空翻，然後撞毀……在此之前，你甚至連減速帶都還沒撞上呢。
BREAKING: Child, Unidentified Creature inBicycle Basket Hit and Killed by Car
突發消息：小孩和自行車籃中的未知生物被車撞擊致死。
If you kept the car from taking off, theforce of the wind at those speeds would strip away the hood, side panels, andwindows. At higher speeds, the car itself would be disassembled, and might evenburn up like a spacecraft reentering the atmosphere.
如果你竭力保持車子不飛起來，在這種速度下，風力會掀開引擎蓋、車體側面以及車窗。在更高的速度下，車子本身會解體，或者像重返大氣層的太空飛船那樣直接燒燬。
What's the ultimate limit?
終極上限是多少？
In the state of Pennsylvania, drivers maysee $2 added to their speeding ticket for every mile per hour by which theybreak the speed limit.
在賓夕法尼亞州，如果你超速吃了罰單，時速每超過限速1英里就要多交2美元罰金。
Therefore, if you drove a car over aPhiladelphia speed bump at 90 percent of the speed of light, in addition todestroying the city . . .
因此，如果你駕車以90％的光速壓過費城的減速帶，除了會毀了整座城市之外……
. . . you could expect a speeding ticket of$1.14 billion.
……你還會收到一張11.4億美元的罰單。
1 Like anyone with a physics background, Ido all my calculations in SI units, but I've gotten too many US speedingtickets to write this answer in anything but miles per hour; it's just beenburned into my brain. Sorry!
1．和所有具有物理背景的人一樣，我的所有計算都使用SI單位制。但是我在美國吃了太多的英制單位罰單，以至於這個答案我只能用英里每小時去寫。有點刻進我腦子裏了。對不起！
2 Just Google “hit a curb at 60.”
2．去谷歌上搜索一下“hit the curb at 60”。
3 There are cars everywhere. Go outsidewith a ruler and check.
3．車子到處都是，不信拿把尺子去量一下。
4 At high speeds, you can easily losecontrol even without hitting a bump. Joey Huneycutt's 220-mph crash left hisCamaro a burned-out hulk.
4．在高速情況下車子極易失控，甚至都不用撞上減速帶。喬伊•霍尼卡特的大黃蜂在以220英里的時速撞毀後被燒得只剩一具空殼。
