WEBVTT - How Mirrors Work 0:00:00.240 --> 0:00:02.880 Brought to you by the reinvented two thousand twelve Camray. 0:00:03.120 --> 0:00:07.480 It's ready. Are you welcome to Stuff you Should Know 0:00:08.080 --> 0:00:16.360 from House Stuff Works dot Com. Hey, and welcome to 0:00:16.440 --> 0:00:20.239 the podcast. I'm Josh Clark, There's Charles W. Chuck Bryant. 0:00:20.600 --> 0:00:24.320 We're about to talk about mirrors. I set up it's 0:00:24.320 --> 0:00:27.200 a SINCU. How are you Were you in the mirrors 0:00:27.240 --> 0:00:29.800 growing up? Now that we said, you know, I did 0:00:29.800 --> 0:00:34.880 it sccinctly, We're gonna just blow like three minutes, right, No, 0:00:35.000 --> 0:00:36.440 I was asking you if you were in the mirrors 0:00:36.680 --> 0:00:39.160 in the mirrors growing up? Yeah, I mean that didn't 0:00:39.159 --> 0:00:41.400 every kid go through a phase where they're like very 0:00:41.440 --> 0:00:44.080 obsessed with their looks and mirrors and things. Oh yeah, 0:00:44.159 --> 0:00:46.400 I was into myself. I wasn't in the mirrors. They 0:00:46.400 --> 0:00:49.440 were just means to end, you know. Yeah, But I 0:00:50.000 --> 0:00:51.360 like I was reading this and I kind of was 0:00:51.400 --> 0:00:54.080 just thinking myself and remembering laughing about I remember being 0:00:54.120 --> 0:00:57.360 like fifteen and like stopping to look at mirrors anytime 0:00:57.360 --> 0:00:59.720 there was one to see what looks like. Yeah, and 0:00:59.760 --> 0:01:02.600 now I just break them. I'd forgotten all about that 0:01:02.640 --> 0:01:04.800 phase of my life though, until you just brought it up, 0:01:05.000 --> 0:01:07.880 remember that. Yeah, it's nice to be able to not 0:01:08.040 --> 0:01:10.000 look at a mirror. Like some days. I'll go out, 0:01:10.680 --> 0:01:12.720 you know, after getting ready in the morning, and I 0:01:12.760 --> 0:01:15.760 have no idea what I actually look like. But I'm 0:01:15.840 --> 0:01:18.640 so and this is um this cross pollination with an 0:01:18.680 --> 0:01:23.520 earlier podcast. I suffered from body dysmorphic disorder so badly 0:01:24.040 --> 0:01:26.200 that I don't really know what I look like anyway. 0:01:27.680 --> 0:01:32.279 I think I look a bit like theme from taxidermia. 0:01:33.440 --> 0:01:38.440 What's that? It's not plusant? Okay, well you don't my friend. 0:01:38.440 --> 0:01:39.679 I don't even know what he looks like, but I 0:01:39.680 --> 0:01:42.960 can tell you don't look like him. I appreciate that, Chuck, Chuck, 0:01:43.480 --> 0:01:45.920 do you want to hear what I had in store? Like? 0:01:45.959 --> 0:01:47.760 I could not come up with an intro for this. 0:01:47.960 --> 0:01:54.160 Let's Websters defines mirror. I'm kidding. I always going to 0:01:54.200 --> 0:01:56.280 say something equally bad, though it was going to be 0:01:56.320 --> 0:02:00.840 something along the lines with mirrors are ubiquitous. I've seen 0:02:01.160 --> 0:02:06.040 at least six of them today. They weren't always that way, though, Chuck. Well, 0:02:06.080 --> 0:02:09.200 it says in the article here the full length mirrors 0:02:09.200 --> 0:02:11.320 have only been around four hundred years. That didn't seem right. 0:02:11.440 --> 0:02:15.600 That's not right, No, um full length mirrors. There is 0:02:15.600 --> 0:02:18.880 a type of full length mirror UM that has been 0:02:18.919 --> 0:02:22.040 around for about four hundred years. Full length mirrors, as 0:02:22.040 --> 0:02:25.080 far as I know, are mirrors capable of reflecting a 0:02:25.120 --> 0:02:27.920 full image of a person, have been around since about 0:02:27.919 --> 0:02:33.160 the first century a D. Actually, UM and mirrors us 0:02:33.600 --> 0:02:39.320 using surfaces, polished surfaces to see our own reflection. UM 0:02:39.440 --> 0:02:43.480 has been around since about six thousand BC. Yeah. The 0:02:43.520 --> 0:02:48.960 earliest ones were found in Anatolia, Turkey, and they're polished obsidian. Yeah, 0:02:48.960 --> 0:02:52.600 it's a volcanic glass. Yeah, so it's it's dark. That's interesting, 0:02:52.639 --> 0:02:54.960 but it's still produced the best reflection, I guess at 0:02:54.960 --> 0:02:57.200 the time. At the time, I mean, you gotta you 0:02:57.240 --> 0:03:00.239 gotta go with what you what we have to work with, right, Well, yeah, 0:03:00.280 --> 0:03:02.920 but then after that they led them to um like 0:03:03.120 --> 0:03:08.080 silver and bronze and copper, polished polished reflection spasics and chuck. 0:03:08.120 --> 0:03:10.600 I don't know if you've ever held a hunk of 0:03:10.600 --> 0:03:16.480 of copper or bronze I haven't, or silver I have. Okay, 0:03:16.520 --> 0:03:19.440 it's heavy, Yeah, it's real heavy. Right. So this actually 0:03:19.480 --> 0:03:24.440 limited the size of mirrors for centuries, right, Yeah, And 0:03:24.480 --> 0:03:26.200 they were just kind of decorative at first two right, 0:03:26.760 --> 0:03:28.840 I think so. And you also had to be extremely 0:03:28.960 --> 0:03:32.920 rich um to own one of these, right um. And 0:03:32.960 --> 0:03:37.120 then around I think the Middle Ages, we became capable 0:03:37.160 --> 0:03:39.720 of making glass, and all of a sudden it was 0:03:39.760 --> 0:03:43.920 like mirror technology just takes a huge leap forward. Well true, 0:03:44.080 --> 0:03:48.400 but not not super uh forward, because the sand was 0:03:48.680 --> 0:03:51.200 pretty impure back then they used to make the glass. 0:03:51.240 --> 0:03:53.680 So I think they, um they said in the article, 0:03:53.760 --> 0:03:56.160 was until like the Renaissance that it kind of really 0:03:56.200 --> 0:03:59.760 started becoming a little more polished, if you will, terrible. 0:03:59.840 --> 0:04:02.880 And then the Venetians are who really you know with 0:04:02.920 --> 0:04:04.800 a glass and everything. They just they just took in 0:04:04.880 --> 0:04:07.600 ran with it. Well. Even still, if you successfully made 0:04:07.600 --> 0:04:12.600 a mirror, um, it was probably extremely expensive as well 0:04:13.120 --> 0:04:16.359 because they were so rare. The process of manufacturing a 0:04:16.400 --> 0:04:20.720 mirror um very infrequently produced a usable mirror. That's what 0:04:20.760 --> 0:04:29.040 you're doing was adhering um melted molten metal onto glass, 0:04:29.320 --> 0:04:32.840 which almost always broke the glass. So when it didn't, 0:04:32.839 --> 0:04:35.159 I'm sure you're just like, oh my god's the first 0:04:35.160 --> 0:04:39.919 one in seven years? Right um? But that when I 0:04:39.960 --> 0:04:41.800 was reading this article, I didn't really think about it. 0:04:41.880 --> 0:04:44.400 That's what a mirror is, isn't it. I've even seen 0:04:44.440 --> 0:04:47.520 the back of mirrors and been like others like metal 0:04:47.839 --> 0:04:50.640 looks like spray painted on the back. That's exactly right. 0:04:51.080 --> 0:04:53.559 And that was the process, um what's it called silver 0:04:53.680 --> 0:04:57.279 ring that was invented by a guy named Justice von 0:04:57.400 --> 0:05:01.400 Liebig and in a team thirty five. If you figured 0:05:01.440 --> 0:05:05.880 out how to spray very thin layer of silver um 0:05:06.000 --> 0:05:08.920 or aluminum on the back or on one side of 0:05:09.160 --> 0:05:13.320 a glass, and they're, my friend, you have the modern mirror. Yeah, 0:05:13.360 --> 0:05:15.000 and now they I think they make it now by 0:05:15.080 --> 0:05:17.839 heating aluminum in a vacuum and kind of much the 0:05:17.880 --> 0:05:21.000 same way or different methods, but the same same concept. 0:05:22.440 --> 0:05:25.320 Go ahead, Well, I wanted to say when when you 0:05:25.360 --> 0:05:29.440 were talking about the Renaissance, the Venetians were they? I 0:05:29.480 --> 0:05:32.880 guess they had the secret of mirrors under wraps like 0:05:32.960 --> 0:05:37.640 the Mason's very much so. Um. And if you were 0:05:37.880 --> 0:05:40.920 a mirror maker and it got out that you had 0:05:41.000 --> 0:05:45.960 told someone how to make mirrors, you were frequently killed. Right, Yeah, 0:05:46.279 --> 0:05:50.359 trade secret. But when mirrors were introduced, um, when good 0:05:50.400 --> 0:05:54.240 mirrors were introduced, not polished obsidian, things changed a little bit, 0:05:54.360 --> 0:05:57.200 especially with art. Right. Yeah, I never really considered that, 0:05:57.240 --> 0:06:00.320 but that it spawned something that would become a mark 0:06:00.320 --> 0:06:03.000 of the art world, which is the self portrait. Right 0:06:03.080 --> 0:06:05.600 before that, you couldn't draw yourself because you could not 0:06:05.640 --> 0:06:09.120 see yourself. That's exactly right, And you could, but I 0:06:09.120 --> 0:06:12.160 mean you're gonna use like maybe a pond or a 0:06:12.200 --> 0:06:14.520 piece of polished medal or something like that. Imagine like 0:06:15.200 --> 0:06:16.960 going out and looking at a pond and going back 0:06:17.000 --> 0:06:19.360 and sitting down now as opposed to having a mirror there. Yes, 0:06:19.440 --> 0:06:24.119 really simplified it. It's also not coincidental that UM good 0:06:24.200 --> 0:06:27.719 mirrors came about at the same time that UM linear 0:06:27.800 --> 0:06:32.719 perspective was introduced into art. Yeah, there's a guy named 0:06:32.880 --> 0:06:39.320 UM Filippo Brunus Brunelleschi. Nice Chuck, thank you for doing that. UM, 0:06:39.360 --> 0:06:43.440 and he he, I guess discovered linear perspective because I 0:06:43.440 --> 0:06:45.159 think it's one of the things that was always there. 0:06:45.720 --> 0:06:49.320 We just stumbled upon it through mirrors. That's how we 0:06:49.360 --> 0:06:51.280 figured it out. Yeah, because if you look at a mirror, 0:06:51.320 --> 0:06:55.680 all of a sudden, linear perspective really comes into focus, right, 0:06:55.839 --> 0:06:58.680 you will. Well, And then scientists UM said, hey, we 0:06:58.720 --> 0:07:02.560 could use these to make like reflecting telescopes, and that 0:07:02.680 --> 0:07:04.360 was what year was at That was a long time ago. 0:07:05.160 --> 0:07:07.800 The first reflecting telescope was invented by a guy named 0:07:07.880 --> 0:07:12.040 James Bradley just off the top of my head. Very 0:07:12.440 --> 0:07:15.640 well then, uh, And the mirrors were also used by 0:07:15.880 --> 0:07:20.400 a very very famous scientist early scientists named Archimedes. Supposedly 0:07:20.960 --> 0:07:23.680 I wrote an article on archimedes death. Ray, Oh did 0:07:23.720 --> 0:07:25.480 you write that? Yeah? Did you ever read it? I 0:07:25.520 --> 0:07:28.000 did back in a while ago, just out of interest? 0:07:28.040 --> 0:07:30.480 How about that? Thanks a lot man? Sure did you 0:07:30.520 --> 0:07:33.320 see in it? Um? Some I can't remember. It was 0:07:33.360 --> 0:07:36.280 one of the Ivy League schools. They tried to set 0:07:36.320 --> 0:07:38.640 things on fire with this system of mirrors, that arch 0:07:40.000 --> 0:07:42.880 that's who it was, and they succeeded. Yes, And the 0:07:42.960 --> 0:07:47.120 MythBusters claimed it was busted, like they set a small fire. 0:07:47.240 --> 0:07:49.320 But I think they busted it because they said it 0:07:49.360 --> 0:07:52.800 wasn't enough to like sink a ship. But m I 0:07:52.840 --> 0:07:54.840 T I mean, they caused quite a fire on that boat. 0:07:55.800 --> 0:07:57.440 And of course they had. I mean I saw this 0:07:57.480 --> 0:08:00.800 set up online today. It was pretty massive. Of Archimedes 0:08:00.840 --> 0:08:03.840 had that kind of technology or at least that many 0:08:03.840 --> 0:08:06.400 mirrors at its disposal, or maybe he did. And plus 0:08:06.440 --> 0:08:09.040 they had I think they used pretty good mirrors too. Yeah, 0:08:09.080 --> 0:08:10.560 well it was legend though. They don't know if the 0:08:10.600 --> 0:08:13.600 Archimedes thing is true. Right, we know that he invented 0:08:13.600 --> 0:08:16.400 the water screw and let's saved countless lives. What's that 0:08:17.080 --> 0:08:21.200 It's a way to deliver water from the ground top side. 0:08:21.320 --> 0:08:24.160 Oh really yeah? Cool? You have to check it out, 0:08:24.200 --> 0:08:28.840 smart dude. Um, so, Chuck, we now know the comprehensive 0:08:29.680 --> 0:08:33.440 broad strokes of the history of mirrors. Right, Yes, let's 0:08:33.440 --> 0:08:35.959 talk about mirror physics. We work for how stuff works 0:08:36.000 --> 0:08:39.440 dot com, which means we're pretty much obligated to discuss 0:08:39.480 --> 0:08:42.360 the physics of whatever we're talking about any time it applies, right, 0:08:42.360 --> 0:08:46.439 And that's true, and mirrors are definitely one of those times. Yes, 0:08:46.800 --> 0:08:49.360 so Chuck take it away. Well, I can cover the 0:08:49.400 --> 0:08:51.559 first part because it makes sense to me. The law 0:08:51.600 --> 0:08:54.400 of reflection um Josh says that when you bounce a 0:08:54.480 --> 0:08:56.960 ray of light off the surface, it bounces back off 0:08:56.960 --> 0:09:00.480 in a certain way, and it is um the angle 0:09:00.480 --> 0:09:03.840 of incidences is when it comes in the angle of reflection, 0:09:03.880 --> 0:09:07.240 it when it bounces off, and it matches so that 0:09:07.320 --> 0:09:09.319 the way they pointed out in the article, which makes 0:09:09.360 --> 0:09:11.599 sense to me is like at sunset, the sun is 0:09:11.679 --> 0:09:13.760 very low on the horizon, so it bounces off at 0:09:13.760 --> 0:09:16.839 a low angle, or approaches the water at a low angle, 0:09:16.880 --> 0:09:18.960 like at a lake, let's say, and then it bounces 0:09:18.960 --> 0:09:20.680 off of that lake at the same low angle, like 0:09:20.760 --> 0:09:23.319 right into your face. But if it seems brighter if 0:09:23.320 --> 0:09:27.319 the sun's overhead though, yeah, the sunlight is coming down 0:09:27.400 --> 0:09:30.120 under the lake and it's reflecting back up basically over 0:09:30.160 --> 0:09:35.800 your head. Yeah, you're looking at a horizontal angle pretty much, 0:09:36.480 --> 0:09:40.040 and this is happening on a vertical angle. Yeah, that's 0:09:40.040 --> 0:09:42.160 why you'll get like more glare at a sunrise or 0:09:42.160 --> 0:09:46.160 a sunset scenario. Um. And what you're saying, the angle 0:09:46.200 --> 0:09:49.439 of incidence equals the angle of reflection, right. Indeed, if 0:09:49.480 --> 0:09:52.480 you take if if a if a beam of light 0:09:53.040 --> 0:09:55.440 is shot at a ninety degree angle or no, let's 0:09:55.440 --> 0:09:58.280 say eighty degree angle, it's gonna bounce off at an 0:09:58.280 --> 0:10:01.640 opposite eighty degree angle. So both are at eighty degrees. 0:10:01.760 --> 0:10:04.480 But if you look at the whole thing, the incidents 0:10:04.559 --> 0:10:06.840 and the reflection, it's going to cover a hundred and 0:10:06.840 --> 0:10:11.520 sixty degrees right, all right. So that's the first part. 0:10:11.559 --> 0:10:15.480 That's that's how That explains how light reacts with the reflection, 0:10:15.559 --> 0:10:18.360 and that's where the smooth surface with with most things 0:10:18.400 --> 0:10:21.400 like say, look at my hand man, take a look 0:10:21.440 --> 0:10:25.640 at these hands. Um, the the the light that's bouncing 0:10:25.679 --> 0:10:27.839 off of them. What's giving us the ability to see 0:10:27.880 --> 0:10:33.400 these huge, awesome hands, Um, is that they're not huge? 0:10:33.400 --> 0:10:37.400 Are they are the smaller than average size? No, they're 0:10:37.400 --> 0:10:39.920 they're bigger than mine. I got small hands. I wouldn't 0:10:39.920 --> 0:10:42.480 see you have small hands. Let's see now those are like, 0:10:43.080 --> 0:10:45.079 those are totally normal. I don't have hair in the 0:10:45.080 --> 0:10:46.760 back of my hands either. I've got hair on my 0:10:46.800 --> 0:10:52.320 first knuckles. Yeah, Robin Williams. Um, what's allowing us to 0:10:52.360 --> 0:10:55.160 see our hands right now and judge their size and 0:10:55.240 --> 0:11:00.400 scale is, um, what's called diffuse reflection, which the light 0:11:00.440 --> 0:11:02.520 that's coming off of all of these light bulbs right 0:11:02.520 --> 0:11:05.800 now are hitting all these different areas, these different services 0:11:05.840 --> 0:11:08.920 on my hands, and it's bouncing off, it's being scattered 0:11:09.040 --> 0:11:13.680 right the mirror the highly reflective surface. Um, what we 0:11:13.800 --> 0:11:18.680 have is called specular reflection, and that is where it's 0:11:18.720 --> 0:11:22.240 pretty close to the law of reflection, where the angles 0:11:22.280 --> 0:11:24.920 coming in at one or the lights coming in at 0:11:24.920 --> 0:11:29.360 one angle, and coming off at the same degree in 0:11:29.400 --> 0:11:33.400 the opposite direction, right, Um, which is why we're allowed 0:11:33.440 --> 0:11:37.000 to see ourselves in a piece of glass with metal 0:11:37.080 --> 0:11:39.800 on the back. And what this creates when you're looking 0:11:39.840 --> 0:11:42.640 at yourself is called the virtual image. Right. I find 0:11:42.679 --> 0:11:45.080 it fascinating. Yeah, me too, and it's a little brain 0:11:45.120 --> 0:11:48.320 melty for me, of course. But at the same time 0:11:48.760 --> 0:11:51.160 you realize, like, well, you've grown up around mirrors the 0:11:51.160 --> 0:11:55.400 whole time, and no one has any real concept of 0:11:55.400 --> 0:11:58.800 of how they work. Right. We just take for granted 0:11:58.840 --> 0:12:01.840 that they do work, but you don't really give much 0:12:01.920 --> 0:12:05.280 thought to how they're working, right, Like the Venus effect. 0:12:05.280 --> 0:12:08.679 Did you read about that? Yeah? That that's explained that 0:12:08.920 --> 0:12:11.480 because this is where when we talk about or actually 0:12:11.520 --> 0:12:14.160 the Venus effect is two different things, and both of 0:12:14.200 --> 0:12:16.200 them kind of melt my brain that the left and 0:12:16.280 --> 0:12:19.439 right being reversed, which is not actually true, and then 0:12:19.440 --> 0:12:21.760 the venus effects. So let's talk about both of those. Okay, Well, 0:12:21.800 --> 0:12:24.800 the Venus effect is basically just shows how little we 0:12:24.920 --> 0:12:28.400 can grasp or how little we grasp mirrors and how 0:12:28.440 --> 0:12:31.000 they work. If you look at um, paintings of the 0:12:31.120 --> 0:12:35.680 Venus de Milo or Venus the goddess um Almost always 0:12:35.679 --> 0:12:38.280 she's holding a hand mirror, and in the painting you 0:12:38.320 --> 0:12:41.040 can see her face in the mirror, but she's looking 0:12:41.080 --> 0:12:44.080 at herself in the mirror, and her face is painted 0:12:44.080 --> 0:12:45.960 in the mirror for the benefit of the viewer. But 0:12:46.040 --> 0:12:49.520 you take for granted that she's viewing herself, when in actuality, 0:12:49.720 --> 0:12:51.800 if you could see Venus's face in the mirror, she 0:12:51.800 --> 0:12:53.800 wouldn't be able to see herself. She'd see you in 0:12:53.840 --> 0:12:58.240 the mirror because of that angle or the law of reflection. Yeah, 0:12:58.280 --> 0:13:00.880 and that's the only way I only understood that was 0:13:00.920 --> 0:13:03.680 when I remembered, like in my film set days, when 0:13:03.720 --> 0:13:07.280 you shoot a person looking in a mirror, they aren't. 0:13:07.520 --> 0:13:09.920 They don't see themselves in the mirror clearly, because he 0:13:09.920 --> 0:13:12.160 would see the camera behind them, so that the mirror 0:13:12.240 --> 0:13:14.840 is angled and it looks like they're looking at themselves 0:13:14.840 --> 0:13:17.080 and primping, but they're not seeing themselves. Pretty cool, right, 0:13:17.920 --> 0:13:20.720 So that makes sense to me now, it does, doesn't it. Okay, 0:13:21.000 --> 0:13:23.960 the other thing you were saying is left and right, Yeah, 0:13:24.000 --> 0:13:26.240 it's not actually left and right. Yeah, this one was 0:13:26.280 --> 0:13:28.080 a little brain melty, but I think I finally got 0:13:28.080 --> 0:13:31.920 it too. Okay, So consider that what you're not what 0:13:31.960 --> 0:13:35.440 you're seeing isn't actually your reflection, but another version of 0:13:35.480 --> 0:13:38.720 yourself in the mirror world. Right. If you look at 0:13:38.720 --> 0:13:41.040 it that way, then the mirror represents the halfway point. 0:13:41.080 --> 0:13:45.400 It's always halfway between you and your virtual self, right, right, 0:13:45.440 --> 0:13:48.320 because your virtual self, that image of yourself in the 0:13:48.360 --> 0:13:52.360 mirror is always twice as it's always two times away 0:13:52.400 --> 0:13:55.480 from you, with the mirror representing the halfway point. Right, 0:13:55.559 --> 0:13:58.360 So your two feet from the mirror and your virtual 0:13:58.360 --> 0:14:00.640 self is another two feet away from you. Right, You 0:14:00.679 --> 0:14:02.800 see what I'm saying. Yeah, And the left and right 0:14:02.840 --> 0:14:04.920 thing isn't really left and right, it's really front and 0:14:04.960 --> 0:14:08.520 back that are reversed. You again, think of yourself as 0:14:08.559 --> 0:14:11.800 the virtual image. Yes, you walk into the mirror world, 0:14:12.160 --> 0:14:14.360 you take you go another two feet away from where 0:14:14.360 --> 0:14:16.920 you were just standing, So you're now your four feet 0:14:16.960 --> 0:14:19.280 away from where you're just standing and turn around, right, 0:14:19.600 --> 0:14:22.960 Which is weird because it actually gives the virtual image 0:14:23.000 --> 0:14:25.440 something of its own identity, doesn't it does. It's a 0:14:25.480 --> 0:14:27.720 little creepy. Yeah, So when you're looking at a mirror, 0:14:27.760 --> 0:14:31.239 you're it's not a reflection of you from the mirrors perspective. 0:14:31.280 --> 0:14:33.760 It's like that. The one example they gave was if 0:14:33.760 --> 0:14:36.040 you wrote something on a piece of paper and then 0:14:36.120 --> 0:14:37.720 held that paper up to the light and looked at 0:14:37.720 --> 0:14:40.160 it from the back, it would appear backwards. But it's 0:14:40.160 --> 0:14:44.200 not right. You're just behind it, yes, isn't it. Yeah, 0:14:44.320 --> 0:14:46.800 it's pretty interesting stuff. And I gotta say when you 0:14:47.120 --> 0:14:52.440 two things, when you mentioned doing mirrors, I said to myself, really, 0:14:52.760 --> 0:14:54.560 And then when we told Jerry what we were doing 0:14:54.560 --> 0:14:57.360 this on, she was like really, yeah, but it's I 0:14:57.400 --> 0:14:59.720 think it's much more interesting than I originally thought. Well again, 0:14:59.760 --> 0:15:02.440 it's like the butterfly swings, you know, like we just 0:15:02.800 --> 0:15:05.240 have to know that if we're gonna understand absolutely everything 0:15:05.280 --> 0:15:08.800 that's going on in the world, which is our mission. Yes. Uh, 0:15:08.840 --> 0:15:12.080 should we talk about curved mirrors now? Yeah, because we 0:15:12.080 --> 0:15:14.560 were talking about virtual images. There's actually a way to 0:15:14.600 --> 0:15:18.200 project a real image where this thing isn't in the mirror. 0:15:18.240 --> 0:15:20.840 It's outside of the mirror, but it's not really there. 0:15:20.880 --> 0:15:24.920 It's a projected image, and that uses um concave mirrors. 0:15:25.000 --> 0:15:29.200 You might be familiar with holograms, right, is that the 0:15:29.280 --> 0:15:33.400 same concept the concave mirrors? And actually, if you want 0:15:33.400 --> 0:15:36.120 to see a really cool example of UM a hologram 0:15:36.120 --> 0:15:40.480 produced by a set of concave and flat mirrors. Um. 0:15:40.560 --> 0:15:44.520 You should type in mirrage in YouTube and look for 0:15:44.560 --> 0:15:46.840 the one that's a lowercase just mirrage and it's a 0:15:46.880 --> 0:15:50.280 little piggy um, and it's pretty cool the demonstration that 0:15:50.320 --> 0:15:53.400 this guy does. Yeah, check that out. But chuck, there's 0:15:53.440 --> 0:15:56.520 concave and convex, right, Yeah. Convex is the one that 0:15:56.560 --> 0:16:00.200 curves outward and uh, it reflects at a wider angle 0:16:00.520 --> 0:16:03.480 near the edges in the center, so things are actually 0:16:03.560 --> 0:16:05.920 smaller and you can cover more areas. So that's why 0:16:05.960 --> 0:16:08.320 they'll use those. Uh, they'll stick them on like your 0:16:08.320 --> 0:16:12.080 passenger mirrors, so you can see more area around your car. 0:16:12.280 --> 0:16:14.640 And it also notes, you know, objects or smaller than 0:16:14.640 --> 0:16:17.680 they appear or closer than they appear. Objects are smaller 0:16:17.680 --> 0:16:20.320 than the appear, but they are smaller than they than 0:16:20.360 --> 0:16:22.800 they appear. But that's not really that doesn't matter. It's 0:16:22.800 --> 0:16:25.400 whether they're like in your back seat or not. Yeah, 0:16:25.440 --> 0:16:27.960 and they actually Um. There are have been rumors over 0:16:27.960 --> 0:16:31.280 the years that department stores put convex mirrors slightly convex 0:16:31.360 --> 0:16:34.600 mirrors in their changing rooms to make you like a pear, tallerant, 0:16:34.600 --> 0:16:36.600 thinner in the clothing that you try on. Remember that 0:16:36.640 --> 0:16:40.000 Seinfeld where Eline like buys that dress, They had a 0:16:40.040 --> 0:16:42.760 skinny mirror, And I think Barneys are blooming deals. Yeah, 0:16:42.800 --> 0:16:44.880 forget about that. Yeah, I don't know. I think that's 0:16:44.880 --> 0:16:48.240 probably urban legend, but who knows, um chuck. The other one, 0:16:48.280 --> 0:16:53.160 like we said, was concave converging. We use this for holograms. 0:16:53.560 --> 0:16:56.320 They also use that to light the Olympic torch. Yeah. 0:16:56.320 --> 0:16:58.080 I didn't realize that either. I think that's a nod 0:16:58.080 --> 0:17:02.280 to Archimedes too, probably, so you're probably a little more 0:17:02.480 --> 0:17:08.439 um acquainted with convex mirrors. No concave mirrors for like 0:17:08.600 --> 0:17:11.840 shaving or No, those horrible mirrors that show your like 0:17:12.000 --> 0:17:15.880 hair into jail. Those are awful, they really are. Don't 0:17:15.880 --> 0:17:19.560 ever look in those nonreversing mirror, which really is pretty simple. 0:17:19.640 --> 0:17:23.960 It's just two mirrors perpendicular to each other, right, Yeah, 0:17:23.960 --> 0:17:27.359 And the deal is with that they meet at the angle, 0:17:27.600 --> 0:17:30.919 and so you technically can see a non reverse image, 0:17:30.920 --> 0:17:33.240 but you've got that line running down the center of you. 0:17:33.800 --> 0:17:37.320 They don't make like a flat, single nonreversing mirror, No, 0:17:37.560 --> 0:17:39.760 they don't. I think it's physically impossible. It's not like 0:17:39.840 --> 0:17:41.639 they don't make it like they're not interested. It's just 0:17:41.680 --> 0:17:43.720 can't be done. But what's funny is there's a guy 0:17:43.960 --> 0:17:49.280 named Um John Derby who has a patent. In seven 0:17:49.280 --> 0:17:51.800 when he was alive, he had a patent for a 0:17:51.840 --> 0:17:55.680 nonreversing mirror. By sticking two mirrors together, I could get 0:17:55.680 --> 0:17:57.520 a patent for that. I could fill out the patent 0:17:57.560 --> 0:18:01.119 application for that. Could Yeah, it's like take mirror A 0:18:01.400 --> 0:18:03.960 and you stick it perpendicular to mirr B right there, 0:18:04.000 --> 0:18:06.720 give me my patent. Well, but then John Derby's family 0:18:06.760 --> 0:18:09.280 would come after you. Hopefully it ran out by now, 0:18:09.320 --> 0:18:13.760 and just for simpleness, Josh, two way mirrors as seen 0:18:13.800 --> 0:18:16.639 in every cop shakedown movie ever made. Yes, now, this 0:18:16.720 --> 0:18:19.640 is fascinating, Chuck. How does the two way mirror work? Well, 0:18:19.720 --> 0:18:22.520 it's really pretty easy. It's just it's the same concept 0:18:22.520 --> 0:18:25.359 of the mirror, but it's a very thin. It's very 0:18:25.440 --> 0:18:29.520 much a lighter reflection the material they use and the 0:18:29.560 --> 0:18:32.520 coated side. When it faces the lit room, some of 0:18:32.560 --> 0:18:35.000 the light reflects and some goes into the dark room 0:18:35.040 --> 0:18:38.800 behind it. So basically, like you know, you can't you 0:18:38.840 --> 0:18:41.359 can see only see one way right because of the 0:18:41.480 --> 0:18:46.520 light mainly, so it's just like very thin reflective surface 0:18:46.520 --> 0:18:49.119 where if you're not if you turn in, if you 0:18:49.160 --> 0:18:51.320 turn on lights in both rooms, you'd be able to 0:18:51.359 --> 0:18:53.720 see through that reflective surface. Right. Yeah, it's all about 0:18:53.720 --> 0:18:56.639 the lighting. And that's a movie there. There's several movie 0:18:56.680 --> 0:18:58.840 mirror things that are done in like every movie, and 0:18:58.880 --> 0:19:02.159 that's one of them with the Coton movie. And inevitably 0:19:02.200 --> 0:19:04.919 the person getting questioned will always walk right up and 0:19:04.960 --> 0:19:06.760 like be staring into the face of the person on 0:19:06.840 --> 0:19:09.320 the other side that they can't see. And then the 0:19:09.359 --> 0:19:13.760 other favorite of mine, which one of the SNL shorts aped, 0:19:13.960 --> 0:19:17.080 was um the classic horror movie scene where you where 0:19:17.119 --> 0:19:19.280 you look in the medicine cabinet in the mirror and 0:19:19.320 --> 0:19:21.720 then you open the medicine cabinet and then you close 0:19:21.800 --> 0:19:24.280 it and the dude is right behind you. That's a classic. 0:19:24.400 --> 0:19:27.440 It is there's UM again on YouTube. I think there's 0:19:27.480 --> 0:19:30.879 a a montage, like a four minute montage of that 0:19:31.080 --> 0:19:34.840 being used over and times. Dude and it still gets people. Yeah, 0:19:34.920 --> 0:19:36.760 but now that the whole spin is to do that 0:19:36.840 --> 0:19:38.920 and then there's not someone there, and then they'll turn 0:19:38.960 --> 0:19:41.800 around and that's where they are something just jerking the 0:19:41.840 --> 0:19:46.320 audience around. That's in there too. Oh it is, huh yeah, yeah, 0:19:46.359 --> 0:19:48.800 it's not just people closing there, someone saying there's ones 0:19:48.800 --> 0:19:51.960 where they're not standing there. Yeah. I love those movie 0:19:52.040 --> 0:19:54.840 conventions that are The other one too, is it doesn't 0:19:54.880 --> 0:19:57.560 even do with mirrors, but the scene where you're where 0:19:57.560 --> 0:19:59.960 someone is searching for the files and then the person 0:20:00.160 --> 0:20:02.840 office after dark and you know they're coming up the 0:20:02.840 --> 0:20:05.919 steps and they opened the door and you're like they're pinched, 0:20:05.960 --> 0:20:07.640 and then they open the door and the person's gone 0:20:07.680 --> 0:20:09.919 and there's like a window open, right, and it's just 0:20:09.960 --> 0:20:13.120 like the curtains. Hundreds and hundreds of time is still 0:20:13.119 --> 0:20:15.600 done yet I'm still like, oh my gosh, here they come. 0:20:16.040 --> 0:20:19.960 What about Poultergeist, the great classic mirror scene of the 0:20:20.000 --> 0:20:22.800 guys like picking at that little clister and ends up 0:20:22.800 --> 0:20:26.400 pulling his whole face off. Yeah that's pretty creepy. Yeah, classic. 0:20:26.520 --> 0:20:30.280 Thank you Toby Hooper. Did he make that? Yeah? I like, oh, 0:20:30.320 --> 0:20:33.119 that's right, he reproduced it, right, that's right. I always 0:20:33.119 --> 0:20:36.879 think he directed that. What else, Chuck, Well, there's some 0:20:36.920 --> 0:20:41.959 superstitions around mirrors in folklore, um summoning bloody Mary by 0:20:42.000 --> 0:20:44.240 saying her names three times in a mirror, or candy 0:20:44.280 --> 0:20:49.800 Man if you're a little more recent, breaking a mirror 0:20:49.800 --> 0:20:54.199 supposedly bad luck because um for seven years, because they 0:20:54.200 --> 0:20:57.439 believe that the soul regenerates every seven years. Yeah, that 0:20:57.680 --> 0:21:00.080 explains it, doesn't it. Yeah, And that's why vampires have 0:21:00.160 --> 0:21:02.600 no soul. That's why they can't see themselves in mirrors. 0:21:02.680 --> 0:21:04.760 And a couple of them I haven't heard of are 0:21:05.680 --> 0:21:07.920 if you give birth and look in a mirror too 0:21:07.920 --> 0:21:11.280 soon afterward, you will see ghostly faces peek out from 0:21:11.280 --> 0:21:14.159 behind the reflection. I've never heard that one in you know, 0:21:14.640 --> 0:21:17.199 I had heard of suiting Shiva though, Yeah, what's the 0:21:17.240 --> 0:21:20.040 deal with that one? Well, if you're Jewish and somebody dies, 0:21:20.119 --> 0:21:22.040 part of the morning process is to cover all the 0:21:22.040 --> 0:21:25.520 mirrors in the house to say that in the talmud. 0:21:26.359 --> 0:21:32.320 Shut up, Chuck. Also, we have gotten conflicting um information 0:21:32.359 --> 0:21:35.639 about whether or not it is taboo among Judaism to 0:21:35.720 --> 0:21:40.600 be cremated. Did you notice? Yeah? And what we and 0:21:40.680 --> 0:21:43.400