[Script Info] Title: [Events] Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text Dialogue: 0,0:00:06.23,0:00:08.74,Default,,0000,0000,0000,,French fries are delicious. Dialogue: 0,0:00:08.74,0:00:12.44,Default,,0000,0000,0000,,French fries with ketchup are a little slice of heaven. Dialogue: 0,0:00:12.44,0:00:15.48,Default,,0000,0000,0000,,The problem is it's basically impossible Dialogue: 0,0:00:15.48,0:00:17.91,Default,,0000,0000,0000,,to pour the exactly right amount. Dialogue: 0,0:00:17.91,0:00:20.04,Default,,0000,0000,0000,,We're so used to pouring ketchup that we don't realize Dialogue: 0,0:00:20.04,0:00:22.56,Default,,0000,0000,0000,,how weird its behavior is. Dialogue: 0,0:00:22.56,0:00:25.88,Default,,0000,0000,0000,,Imagine a ketchup bottle filled with a straight up solid like steel. Dialogue: 0,0:00:25.88,0:00:29.53,Default,,0000,0000,0000,,No amount of shaking would ever get the steel out. Dialogue: 0,0:00:29.53,0:00:32.74,Default,,0000,0000,0000,,Now imagine that same bottle full of a liquid like water. Dialogue: 0,0:00:32.74,0:00:34.54,Default,,0000,0000,0000,,That would pour like a dream. Dialogue: 0,0:00:34.54,0:00:37.04,Default,,0000,0000,0000,,Ketchup, though, can't seem to make up its mind. Dialogue: 0,0:00:37.04,0:00:38.91,Default,,0000,0000,0000,,Is it is a solid? Or a liquid? Dialogue: 0,0:00:38.91,0:00:41.74,Default,,0000,0000,0000,,The answer is, it depends. Dialogue: 0,0:00:41.74,0:00:45.04,Default,,0000,0000,0000,,The world's most common liquids like water, oils and alcohols Dialogue: 0,0:00:45.04,0:00:47.77,Default,,0000,0000,0000,,respond to force linearly. Dialogue: 0,0:00:47.77,0:00:51.14,Default,,0000,0000,0000,,If you push on them twice as hard, they move twice as fast. Dialogue: 0,0:00:51.14,0:00:54.60,Default,,0000,0000,0000,,Sir Isaac Newton, of apple fame, first proposed this relationship, Dialogue: 0,0:00:54.60,0:00:57.96,Default,,0000,0000,0000,,and so those fluids are called Newtonian fluids. Dialogue: 0,0:00:57.96,0:01:00.68,Default,,0000,0000,0000,,Ketchup, though, is part of a merry band of linear rule breakers Dialogue: 0,0:01:00.68,0:01:03.31,Default,,0000,0000,0000,,called Non-Newtonian fluids. Dialogue: 0,0:01:03.31,0:01:05.88,Default,,0000,0000,0000,,Mayonnaise, toothpaste, blood, pain, peanut butter Dialogue: 0,0:01:05.88,0:01:10.08,Default,,0000,0000,0000,,and lots of other fluids respond to force non-linearly. Dialogue: 0,0:01:10.08,0:01:12.01,Default,,0000,0000,0000,,That is, their apparent thickness changes Dialogue: 0,0:01:12.01,0:01:15.28,Default,,0000,0000,0000,,depending on how hard you push, or how long, or how fast. Dialogue: 0,0:01:15.28,0:01:18.71,Default,,0000,0000,0000,,And ketchup is actually Non-Newtonian in two different ways. Dialogue: 0,0:01:18.71,0:01:23.17,Default,,0000,0000,0000,,Way number one: the harder you push, the thinner ketchup seems to get. Dialogue: 0,0:01:23.17,0:01:24.68,Default,,0000,0000,0000,,Below a certain pushing force, Dialogue: 0,0:01:24.68,0:01:27.15,Default,,0000,0000,0000,,ketchup basically behaves like a solid. Dialogue: 0,0:01:27.15,0:01:29.24,Default,,0000,0000,0000,,But once you pass that breaking point, Dialogue: 0,0:01:29.24,0:01:33.64,Default,,0000,0000,0000,,it switches gears and becomes a thousand times thinner than it was before. Dialogue: 0,0:01:33.64,0:01:35.64,Default,,0000,0000,0000,,Sound familiar right? Dialogue: 0,0:01:35.64,0:01:39.48,Default,,0000,0000,0000,,Way number two: if you push with a force below the threshold force Dialogue: 0,0:01:39.48,0:01:41.77,Default,,0000,0000,0000,,eventually, the ketchup will start to flow. Dialogue: 0,0:01:41.77,0:01:45.34,Default,,0000,0000,0000,,In this case, time, not force, is they key to releasing ketchup Dialogue: 0,0:01:45.34,0:01:47.44,Default,,0000,0000,0000,,from its glassy prison. Dialogue: 0,0:01:47.44,0:01:49.37,Default,,0000,0000,0000,,Alright, so, why does ketchup act all weird? Dialogue: 0,0:01:49.37,0:01:52.80,Default,,0000,0000,0000,,Well, it's made from tomatoes, pulverized, smashed, thrashed Dialogue: 0,0:01:52.80,0:01:55.51,Default,,0000,0000,0000,,utterly destroyed tomatoes. Dialogue: 0,0:01:55.51,0:01:56.92,Default,,0000,0000,0000,,See these tiny particles? Dialogue: 0,0:01:56.92,0:01:58.40,Default,,0000,0000,0000,,This is what remains of tomatoes cells Dialogue: 0,0:01:58.40,0:01:59.91,Default,,0000,0000,0000,,after they go through the ketchup treatment. Dialogue: 0,0:02:01.02,0:02:03.25,Default,,0000,0000,0000,,And the liquid around those particles? Dialogue: 0,0:02:03.25,0:02:06.72,Default,,0000,0000,0000,,That's mostly water and some vinegar, sugar, and spices. Dialogue: 0,0:02:06.72,0:02:08.31,Default,,0000,0000,0000,,When ketchup is just sitting around, Dialogue: 0,0:02:08.31,0:02:11.79,Default,,0000,0000,0000,,the tomato particles are evenly and randomly distributed. Dialogue: 0,0:02:11.79,0:02:14.18,Default,,0000,0000,0000,,Now, let's say you apply a week force very quickly. Dialogue: 0,0:02:14.18,0:02:15.68,Default,,0000,0000,0000,,The particles bump into each other, Dialogue: 0,0:02:15.68,0:02:17.48,Default,,0000,0000,0000,,but can't get out of each other's way, Dialogue: 0,0:02:17.48,0:02:18.98,Default,,0000,0000,0000,,so the ketchup doesn't flow. Dialogue: 0,0:02:18.98,0:02:21.98,Default,,0000,0000,0000,,Now, let's say you apply a strong force very quickly. Dialogue: 0,0:02:21.98,0:02:24.85,Default,,0000,0000,0000,,That extra force is enough to squish the tomato particles, Dialogue: 0,0:02:24.85,0:02:26.16,Default,,0000,0000,0000,,so maybe instead of little spheres, Dialogue: 0,0:02:26.16,0:02:29.01,Default,,0000,0000,0000,,they get smushed into little ellipses, and boom! Dialogue: 0,0:02:29.01,0:02:31.14,Default,,0000,0000,0000,,Now you have enough space for one group of particles Dialogue: 0,0:02:31.14,0:02:34.41,Default,,0000,0000,0000,,to get passed others and the ketchup flows. Dialogue: 0,0:02:34.41,0:02:37.90,Default,,0000,0000,0000,,Now let's say you apply a very weak force but for a very long time. Dialogue: 0,0:02:38.44,0:02:41.50,Default,,0000,0000,0000,,Turns out, we're not exactly sure what happens in this scenario. Dialogue: 0,0:02:41.50,0:02:45.21,Default,,0000,0000,0000,,One possibility is that the tomato particles near the walls of the container Dialogue: 0,0:02:45.21,0:02:47.50,Default,,0000,0000,0000,,slowly get bumped towards the middle, Dialogue: 0,0:02:47.50,0:02:49.10,Default,,0000,0000,0000,,leaving the soup they were dissolved in, Dialogue: 0,0:02:49.10,0:02:50.67,Default,,0000,0000,0000,,which remember is basically water, Dialogue: 0,0:02:50.67,0:02:51.94,Default,,0000,0000,0000,,near the edges. Dialogue: 0,0:02:51.94,0:02:54.74,Default,,0000,0000,0000,,That water serves as a lubricant betwen the glass bottle Dialogue: 0,0:02:54.74,0:02:56.56,Default,,0000,0000,0000,,and the center plug of ketchup, Dialogue: 0,0:02:56.56,0:02:59.30,Default,,0000,0000,0000,,and so the ketchup flows. Dialogue: 0,0:02:59.30,0:03:02.04,Default,,0000,0000,0000,,Another possibility is that the particles slowly rearrange themselves Dialogue: 0,0:03:02.04,0:03:05.75,Default,,0000,0000,0000,,into lots of small groups, which then flow past each other. Dialogue: 0,0:03:05.75,0:03:08.64,Default,,0000,0000,0000,,Scientists who study fluid flows are still actively researching Dialogue: 0,0:03:08.64,0:03:11.53,Default,,0000,0000,0000,,how ketchup and its merry friends work. Dialogue: 0,0:03:11.53,0:03:13.58,Default,,0000,0000,0000,,Ketchup basically gets thinner the harder you push, Dialogue: 0,0:03:13.58,0:03:16.64,Default,,0000,0000,0000,,but other substances like oobleck or some natural peanut butters Dialogue: 0,0:03:16.64,0:03:19.67,Default,,0000,0000,0000,,actually get thicker the harder you push. Dialogue: 0,0:03:19.67,0:03:21.87,Default,,0000,0000,0000,,Others can climb up rotating rods, Dialogue: 0,0:03:21.87,0:03:24.24,Default,,0000,0000,0000,,or continue to pour themselves out of a beeker, Dialogue: 0,0:03:24.24,0:03:26.16,Default,,0000,0000,0000,,once you get them started. Dialogue: 0,0:03:26.16,0:03:27.60,Default,,0000,0000,0000,,From a physics perspective, though, Dialogue: 0,0:03:27.60,0:03:30.42,Default,,0000,0000,0000,,ketchup is one of the more complicated mixtures out there. Dialogue: 0,0:03:30.42,0:03:32.47,Default,,0000,0000,0000,,And as if that weren't enough, the balance of ingredients Dialogue: 0,0:03:32.47,0:03:35.57,Default,,0000,0000,0000,,and the presence of natural thickeners like xanthan gum, Dialogue: 0,0:03:35.57,0:03:38.16,Default,,0000,0000,0000,,which is also found in many fruit drinks and milkshakes, Dialogue: 0,0:03:38.16,0:03:39.40,Default,,0000,0000,0000,,can mean that two different ketchups Dialogue: 0,0:03:39.40,0:03:41.80,Default,,0000,0000,0000,,can behave completely differently. Dialogue: 0,0:03:41.80,0:03:43.96,Default,,0000,0000,0000,,But most will show two telltale properties: Dialogue: 0,0:03:43.96,0:03:46.48,Default,,0000,0000,0000,,sudden thinning at a threshold force, Dialogue: 0,0:03:46.48,0:03:48.50,Default,,0000,0000,0000,,and more gradual thinning after a small force Dialogue: 0,0:03:48.50,0:03:50.67,Default,,0000,0000,0000,,is applied for a long time. Dialogue: 0,0:03:50.67,0:03:53.38,Default,,0000,0000,0000,,And that means you could get ketchup out of the bottle in two ways. Dialogue: 0,0:03:53.38,0:03:56.32,Default,,0000,0000,0000,,Either give it a series of long, slow languid shakes Dialogue: 0,0:03:56.32,0:03:58.67,Default,,0000,0000,0000,,making sure you don't ever stop applying force, Dialogue: 0,0:03:58.67,0:04:01.94,Default,,0000,0000,0000,,or you could hit the bottle once very, very hard. Dialogue: 0,0:04:01.94,0:04:04.64,Default,,0000,0000,0000,,What the real pros do is keep the lid on, Dialogue: 0,0:04:04.64,0:04:07.04,Default,,0000,0000,0000,,give the bottle a few short, sharp shakes Dialogue: 0,0:04:07.04,0:04:08.89,Default,,0000,0000,0000,,to wake up all those tomato particles, Dialogue: 0,0:04:08.89,0:04:10.54,Default,,0000,0000,0000,,and then take the lid off Dialogue: 0,0:04:10.54,0:04:20.54,Default,,0000,0000,0000,,and do a nice controlled pour onto their heavenly fries. Dialogue: 0,0:04:20.54,9:59:59.99,Default,,0000,0000,0000,,