1 00:00:00,000 --> 00:00:08,320 Hey guys, welcome to NASA Connect, the show that connects you to the world of math, science, 2 00:00:08,320 --> 00:00:09,640 technology, and NASA. 3 00:00:09,640 --> 00:00:11,200 He's Van Hughes. 4 00:00:11,200 --> 00:00:12,680 And she's Jennifer Pulley. 5 00:00:12,680 --> 00:00:15,520 We're your hosts, along with Norbert. 6 00:00:15,520 --> 00:00:18,760 He's going to help us take you through another awesome episode of NASA Connect. 7 00:00:18,760 --> 00:00:19,760 Right. 8 00:00:19,760 --> 00:00:24,120 Every time Norbert appears, have your cue cards and your brain ready to look for answers 9 00:00:24,120 --> 00:00:26,040 to the questions he gives you. 10 00:00:26,040 --> 00:00:31,200 And teachers, when Norbert appears with a remote, that's your cue to pause the video 11 00:00:31,200 --> 00:00:33,280 and think about the problems he gives you. 12 00:00:33,280 --> 00:00:34,280 Got it? 13 00:00:34,280 --> 00:00:35,280 Oh yeah. 14 00:00:35,280 --> 00:00:36,280 I got it. 15 00:00:36,280 --> 00:00:37,840 Today we're in Kitty Hawk, North Carolina. 16 00:00:37,840 --> 00:00:43,160 This is where the Wright Brothers took the very first controlled, powered flight in 1903. 17 00:00:43,160 --> 00:00:44,160 And guess what? 18 00:00:44,160 --> 00:00:45,160 What? 19 00:00:45,160 --> 00:00:47,360 They used mathematics, like ratios. 20 00:00:47,360 --> 00:00:48,360 What is a ratio? 21 00:00:48,360 --> 00:00:49,360 Good question. 22 00:00:49,360 --> 00:00:53,360 A ratio is a pair of numbers that is used to make comparisons. 23 00:00:53,360 --> 00:00:56,480 And ratios are everywhere. 24 00:00:56,480 --> 00:00:57,480 Get this. 25 00:00:57,480 --> 00:01:02,240 Before the Wright Brothers flew planes, they were experts in one of the most revolutionary 26 00:01:02,240 --> 00:01:05,920 means of travel since the wheel, the bicycle. 27 00:01:05,920 --> 00:01:11,280 So in memory of the Wright Brothers' pre-flight days, let's use this bike as an example of 28 00:01:11,280 --> 00:01:12,280 a ratio. 29 00:01:12,280 --> 00:01:13,760 Good idea, Van. 30 00:01:13,760 --> 00:01:19,680 Let's say we want to compare the number of revolutions, or complete circles, that one 31 00:01:19,680 --> 00:01:23,800 tire makes to the distance that the bike travels. 32 00:01:23,800 --> 00:01:28,040 Pretend this wheel measures 76 centimeters, or 30 inches. 33 00:01:28,040 --> 00:01:33,600 By measuring the distance that the wheel rolled after one revolution, you can set up a ratio. 34 00:01:33,600 --> 00:01:36,640 One revolution to 239 centimeters. 35 00:01:36,640 --> 00:01:37,640 Right. 36 00:01:37,640 --> 00:01:40,360 When you find ratios, you're also using proportions. 37 00:01:40,360 --> 00:01:45,760 A proportion is a number sentence or equation that states that two ratios are equal. 38 00:01:45,760 --> 00:01:49,800 How could you use ratios and proportions to determine how far your bike would travel 39 00:01:49,800 --> 00:01:52,200 if the wheel made five revolutions? 40 00:01:52,200 --> 00:01:53,200 Simple. 41 00:01:53,200 --> 00:01:55,960 Set up a proportion like this. 42 00:01:55,960 --> 00:02:03,840 One revolution to 239 centimeters equals five revolutions to X, which is the unknown distance. 43 00:02:03,840 --> 00:02:11,480 Now, by cross-multiplying, we can see that the wheel would roll 1,195 centimeters in 44 00:02:11,480 --> 00:02:13,080 five revolutions. 45 00:02:13,080 --> 00:02:15,640 Notice that the fraction ratios are equivalent. 46 00:02:15,640 --> 00:02:18,720 Hey, here's another problem for you to try. 47 00:02:18,720 --> 00:02:25,000 If your bike wheel makes one revolution and travels 239 centimeters, how many revolutions 48 00:02:25,000 --> 00:02:30,560 would your wheel make if you traveled 2,352.3 inches? 49 00:02:30,560 --> 00:02:32,760 Be sure to watch your units. 50 00:02:32,760 --> 00:02:36,760 So now that you have a better understanding of ratios and proportions, let's get back 51 00:02:36,760 --> 00:02:43,040 to the Wright Brothers. 52 00:02:43,040 --> 00:02:48,280 How did mathematics and ratios help the Wright Brothers test and design their glider? 53 00:02:48,280 --> 00:02:51,760 Before Flyer 1, the Wright Brothers worked on bicycles. 54 00:02:51,760 --> 00:02:56,040 As young men, Orville and Wilbur started a bicycle manufacturing and repair company in 55 00:02:56,040 --> 00:02:58,300 their hometown of Dayton, Ohio. 56 00:02:58,300 --> 00:03:02,760 The Wright Brothers used the money they made to finance their interest in aviation. 57 00:03:02,760 --> 00:03:07,160 In the winter of 1901, Orville and Wilbur Wright used their knowledge of math to build 58 00:03:07,160 --> 00:03:10,520 a wind tunnel in order to study how to control an aircraft. 59 00:03:10,520 --> 00:03:13,720 It was then that they realized the importance of ratios. 60 00:03:13,720 --> 00:03:14,720 Right. 61 00:03:14,720 --> 00:03:18,000 The Wright Brothers used something called the aspect ratio. 62 00:03:18,000 --> 00:03:22,200 That is the ratio of the wing's length to the wing's width. 63 00:03:22,200 --> 00:03:26,840 By increasing the length of the wing and at the same time decreasing the width of the 64 00:03:26,840 --> 00:03:31,920 wing, the Wright Brothers cut the drag they experienced in their wind tunnel by half. 65 00:03:31,920 --> 00:03:36,040 Immediately, they began designing a better working glider. 66 00:03:36,040 --> 00:03:40,760 In 1903, after adding a rudder, an engine, and a propeller to their aircraft, the Wright 67 00:03:40,760 --> 00:03:45,320 Brothers achieved the first self-propelled flight of an airplane and began the era of 68 00:03:45,320 --> 00:03:46,120 powered flight.