French fries are delicious. French fries with ketchup are a little slice of heaven.
我们都知道炸薯条很好吃，再配上番茄酱简直就是人间美味。
The problem is it's basically impossible to pour exactly the right amount.
但问题是挤出适量的番茄酱实在是太难了。
We're so used to pouring ketchup that we don't realize how weird its behavior is.
我们平时经常挤番茄酱，但是从来没注意到过它有多么的奇怪。
Imagine a ketchup bottle filled with a straight up solid like steel.
想像你的番茄酱瓶里装的是固体，比如不锈钢。
No amount of shaking would ever get the steel out.
不管你怎么摇晃，不锈钢都不会出来。
Now imagine that same bottle full of a liquid like water.
现在再想像一下番茄酱瓶子装水。
That would pour like a dream.
把水倒出来简直易如反掌。
Ketchup, though, can't seem to make up its mind.
但是番茄酱呢，好像很纠结。
Is it is a solid? Or a liquid?
它到底是固体？还是液体？
The answer is, it depends.
答案是，看情况。
The world's most common fluids like water, oils and alcohols respond to force linearly.
这世界上最常见的液体，比如水、油还有酒精，会对力的作用产生线性反应。
If you push on them twice as hard, they move twice as fast.
如果你用两倍的力去挤它们，它们就会以两倍的速度流出来。
Sir Isaac Newton, of apple fame, first proposed this relationship, and so those fluids are called Newtonian fluids.
因为苹果而出名的艾萨克·牛顿先生，首次提出了上述现象，所以它们被称为牛顿流体。
Ketchup, though, is part of a merry band of linear rule breakers called Non-Newtonian fluids.
番茄酱呢，却是线性规则破坏者小团体中的一员，称为非牛顿流体。
Mayonnaise, toothpaste, blood, paint, peanut butter and lots of other fluids respond to force non-linearly.
蛋黄酱，牙膏，血液，颜料，花生酱还有其他很多流体，都不会对力的作用产生线性反应。
That is, their apparent thickness changes depending on how hard you push, or how long, or how fast.
也就是说，它们的浓度会根据你的用力大小，时间和速度改变。
And ketchup is actually Non-Newtonian in two different ways.
事实上，番茄酱会表现出两种非牛顿流体现象。
Way number one: the harder you push, the thinner ketchup seems to get.
现象一：你越用力挤，番茄酱越稀。
Below a certain pushing force, ketchup basically behaves like a solid.
但是如果力道小到特定程度，番茄酱看起来就像固体一样了。
But once you pass that breaking point, it switches gears and becomes a thousand times thinner than it was before.
但是一旦超过了那个临界点，它就摇身一变，变得比刚才稀很多。
Sound familiar right?
听起来很耳熟吧？
Way number two: if you push with a force below the threshold force eventually, the ketchup will start to flow.
现象二：如果你的力道没有达到临界点，番茄酱最后还是会流出来的
In this case, time, not force, is the key to releasing ketchup from its glassy prison.
这种情况下，时间是挤出番茄酱的关键，而不是力。
Alright, so, why does ketchup act all weird?
好吧，那番茄酱到底为什么这么与众不同呢？
Well, it's made from tomatoes, pulverized, smashed, thrashed, utterly destroyed tomatoes.
嗯，首先，它是番茄做的。番茄经过各种切碎，挤压，搅拌之后变得面目全非。
See these tiny particles?
看到这些小颗粒了吗？
This is what remains of tomatoes cells after they go through the ketchup treatment.
它们是在番茄被各种处理后残留下来的番茄细胞。
And the liquid around those particles?
那么这些小颗粒周围的液体呢？
That's mostly water and some vinegar, sugar, and spices.
大部分都是水，还有一些醋，糖，以及香料。
