流言终结者（2003）

MythBusters S13E08

Part 4 Dec. 17, 2020, 12:56 p.m.

and not more ice.
而不是增加后膛厚度
They're scaling down the black powder
他们将火♥药♥量
from 8 to a mere 1.25 ounces.
由225克减至只有35克
If the 20-inch breech can't handle this...
如果51厘米的后膛仍然无法承受...
All right, our cannon is hot.
好了我们的大炮准备就绪
the myth is surely busted.
那么这条流言肯定被终结了
In three, two, one.
倒数三二一
I think it did it. It worked!
我想它做到了成功了
We shot the plug out without blowing up the breech!
这次后膛没有和火♥药♥一起爆♥炸♥
It was a somewhat less-than-big boom, but it's a start.
这算不上什么大爆♥炸♥ 但却开了个好头
Our breech hasn't exploded.
我们的后膛没有爆♥炸♥
It's still intact, which means it's reusable.
仍然完好无损意味着它可以重复使用
We're gonna keep going. 1.75 is next.
我们继续这回放入50克
All right, ice breech locked and loaded.
好了冰制后膛填弹完毕锁定目标
Let's do this.
我们开始吧
In three, two, one.
倒数三二一
Now, that was more aggressive.
这次更剧烈些
But can a brand-new breech contain 2 ounces?
但一个全新的后膛能承受57克火♥药♥吗
2 ounces, in three, two, one.
57克火♥药♥ 倒数三二一
Oh. All right, it looks like that was too much.
好吧看来这就有点太多了
I guess one and three-quarter ounces, that's the perfect amount.
那么50克就是最佳剂量了
Yeah, two is just a bit too much.
没错 57克有点多了
So, we've got the ball.
我们准备好了炮弹
We've got the amount of black powder.
合适剂量的火♥药♥
We've got the size of the breech.
以及合适尺寸的后膛
You know what that means.
知道这意味着什么吗
That means it's time to build a full-size cannon
这意味着现在该建一个全尺寸的大炮
and go for it.
并大胆一试了
Later...
稍后...
Okay, wait, ooh.
好了等等
the game of moans...
怨声载道...
What the xx?
搞毛啊
Nothing's making any sense.
全都没有意义
continues.
继续上演
One.
一
Adam and jamie have a super-sized ping-pong popgun,
亚当和杰米有一支超大尺寸乒乓球玩具枪
and they're not afraid to use it.
而且他们用起来毫无顾忌
But while shooting aesthetically pleasing objects
虽然以每小时720公里的速度
at 450 miles an hour is impressive,
射击各种物体的效果令人印象深刻
they determined the resulting destruction is less than lethal.
但他们认为其产生的破坏力并不致命
So, what next?
那么接下来是什么呢
It might break a rib, but it's not gonna kill you.
它可能会导致肋骨骨折但肯定不致命
Well, Adam has chanced upon
亚当偶然发现了
a cutting-edge resource called the, er, Internet.
一种叫做互联网的"前沿科技资源"
That's amazing.
太神奇了
It turns out that physics teachers
看来物理老师们
have been getting incredible acceleration
不需要24米长的管子
out of ping-pong balls without using 80-foot-long barrels.
就能让乒乓球获得超大加速度了
And I think it's a method that we should investigate immediately.
我觉得我们应该立刻来检验一下
Okay, cool, it's working all right.
好了不错运转正常
What they've been doing is,
他们的方法是
they've been taking a 36-inch-long tube of PVC,
准备一根90厘米长的聚氯乙烯管
and they've been putting a ping-pong ball in one end.
把乒乓球放在一端
Then, they put packing tape over each end of the tube
然后在管子两端贴上胶带
and they use a vacuum to draw a full vacuum in that tube.
用真空吸尘器吸空管子里的空气
Okay.
明白
Here we go. Pulling the vacuum.
好了打开真空吸尘器
Then, when they pierce that side, of course,
然后当他们捅破一端的胶带后
air wants to rush in to fill the vacuum,
空气就会进入填补真空空间
but the ping-pong ball's in the way.
但乒乓球挡在了中间
So, it starts to move forward.
因此它会被往前推动
Just, everyone back off a little bit.
大家都往后退点儿
There's nothing in its way in terms of air
因为是真空的所以乒乓球前方
because there's a vacuum.
没有任何气体阻碍
And so, it bursts out of this side
所以它从这端喷出时的速度
at something over 300 miles per hour.
超过了每小时480公里
That's the theory.
这只是理论
Here we go!
开始了
Holy xx!
太牛逼了
Oh, man, that was really good.
天哪真是不错啊
I didn't expect it to work that well.
没想到这方法这么管用
The 3-foot prototype worked scarily well.
90厘米管子的实验效果惊人
Popping the sealed vacuum caused a sudden influx of air,
戳破密封的真空空间后空气突然涌入
and the pressure differential sends the ball rocketing.
由此产生的压力的变化使乒乓球飞速向前
And after a few technique tweaks...
在几次技术性调整...
One.
一
One.
一
and a double-barrel length...
以及把管子增长一倍后...
One!
一
Adam measures rocketing at
亚当测量到的球速是
375 miles an hour.
每小时600公里
That is mighty respectable.
真是相当惊人
Respectable enough to be the new
惊人到成为新的乒乓球
ping-pong projectile power of choice.
弹射动力最佳选择
Well, the vacuum trick for launching a ping-pong ball
利用真空吸尘器
out of a short length of tubing is working gangbusters.
将乒乓球射出短管的方法非常成功
I actually got 375 miles an hour on a ping-pong ball
乒乓球射出这个仅180厘米长的管子时
out of this measly 6-foot tube.
速度达到了每小时600公里
That is awesome,
这太厉害了
and this is where I'm gonna concentrate my energy
接下来我要集中精力
to get the fastest ping-pong ball possible.
让乒乓球移♥动♥得最快
All right, we're ready.
好了准备好了
Based on the theory that bigger barrels are better...
根据管子越大越好的理论...
Heh, it's taking a little longer to pump this out. Yeah.
把它抽空要多花些时间了是啊
the guys have rigged the vacuum pump to their enormous 80-footer.
他们把真空泵装在了巨大的24米长管上
There's plenty of nerves.
他们忧心忡忡
This has never been done before.
以前从没这么做过
It's scary.
有点怕怕
High expectations...
他们翘首期盼...
Here's a world first.
世界首例即将呈现
and energy waiting to fulfill its potential.
真空管中聚集的能力也蓄势待发
Ping-pong bazooka in three, two, one!
乒乓球火箭筒发射倒数三二一
But it's an unexpected and disappointing dud.
但是这是一发出乎意料又让人失望的哑弹
Ah. That's no good.
这次不行
Here's our ping-pong ball.
这是我们的乒乓球
That wall is where we want the ping-pong ball
那边是我们希望乒乓球
to be embedded in.
击中的墙壁
One!
一
Something's not working.
此事必有蹊跷
But it's reaching close to the end of our tube,
它已经很靠近管道的出口了
and then somehow bouncing back a little.
然后却莫名其妙地开始向后弹
Well, not somehow.
其实并非莫名其妙
See, air rushes in this tube behind the ping-pong ball.
瞧空气从乒乓球后部涌入管中
There's a vacuum in front of it.
而它的前面就是真空
But that air sneaks past the ping-pong ball,
但是空气从间隙越过了乒乓球
and it looks like it's providing a cushion
然后起到了一个缓冲的作用
that's actually causing it to spring back
这使得乒乓球一到出口处就
once it reaches the end.
弹了回来
So, it's not attaining enough speed or momentum to bust out.
它的速度或动量不足以它冲出去
One. Nope.
一不行
Didn't make it.
还是不行
That tells me that we've made this tube too long.
这说明我们把管道做得太长了
Yep, that cushion of air decelerates the ball
是的这个气垫令乒乓球减速
to the point that it doesn't have the force
到力量不足以冲破
to pop the packing tape.
封口的胶带
So, as Brody wouldn't say,
与期待相反
they need a shorter barrel.
他们需要短一点的管道
The question is how short?
问题是多短合适呢
We're gonna use the high-speed camera to find out
我们将利用高速摄像机来找出
where the ping-pong ball is no longer accelerating.
乒乓球在哪里速度最高