Houston Museum of Natural Science is live!

[00:00:00]Turn the camera around.

[00:00:01]>> Let's see how electric the crowd is.

[00:00:04]>> All right. So, we need some volunteers.

[00:00:07]>> Come on up.

[00:00:08]>> Come on up.

[00:00:11]>> So, I need you guys line up here. If you will back here, everybody.

[00:00:19]>> All right. And then what I'm going to have you do is >> try to get the sound better for y'all.

[00:00:27]>> All right. So, hold on to that. You hold on to that. And the rest of you, hold hands. Um, this >> Wow.

[00:00:38]>> We got one, two, three, four, five.

[00:00:42]>> So, what's going on?

[00:00:45]>> So, they just magic electricity is flowing through, >> right? And electricity, but what's actually flowing is electrons are shooting through all of you guys and you're making a complete circle, a complete circuit and therefore um it turns on to it turns white. What happens if we break a circle or if we put in something that the electrons don't >> unless electrons flow easily or it doesn't um it's so exciting >> 250 years old here you know right all right so why don't you two hold What's happening?

[00:01:38]>> So, what happened?

[00:01:41]>> A side circuit. Hold on to it again.

[00:01:47]>> Not enough. I'm not electric anymore.

[00:01:51]>> So, would you guys say that works? Does it let the >> Trying to work on the audio for you guys. Hang tight.

[00:01:58]>> Okay.

[00:02:00]>> Okay. Well, I've got a no pocket. And I'm going to put that in the no pocket.

[00:02:03]What else have I got?

[00:02:08]>> All right, let me try that.

[00:02:14]>> You guys connect again.

[00:02:17]>> Hold on to that. And what do we got? Is it working?

[00:02:22]>> No. No. So good. No good.

[00:02:26]>> It's probably going to be about the best I can do, y'all.

[00:02:28]>> For the audio at least.

[00:02:32]about metal maybe to great. Let's hold it up high so everybody can see what's going on with that energy stick.

[00:02:43]Cool. That works.

[00:02:46]>> So what makes why are we good connect good conductors? What's in us that makes us good conductors? Right? That water and salt water especially makes us very good conductors. So >> do we want to go outside in a thunderstorm? No, >> no. Because there's a lot of the lightning and the electricity is trying to find other conductors, >> which could be >> us.

[00:03:12]Not something we want to do.

[00:03:14]>> One more thing.

[00:03:15]>> Go for it. Oh yeah. Sorry. Something else.

[00:03:20]>> Oh my goodness.

[00:03:21]>> It's rubber.

[00:03:24]Squeeze that real hard.

[00:03:27]>> Doesn't even let the electrons through.

[00:03:28]Okay, put down the no. I got one more thing though. Can we try that?

[00:03:32]Absolutely.

[00:03:34]>> Okay. Can you take your finger like this? Touch her nose. You can get yours down.

[00:03:39]And y'all hold hands. Just touch her nose. Everybody holding hands. Hold on to that really good. And it's working even on the nose. Even when you touch your nose. All right, you kids. You did great. Thank you.

[00:03:57]>> All right.

[00:04:00]Yeah. Okay. So, next we're going to talk about a little static electricity. You guys know about that, huh?

[00:04:06]>> How about Yeah.

[00:04:08]How about in the winter time? You know about static electricity? The conditions are just right, aren't they? It's kind of cold and dry outside. Yeah. And you rub your feet and maybe touch your friend and what happens? Get that little shot. Exactly.

[00:04:24]Some bad girls.

[00:04:26]So that electricity that is all around us. These electrons are all moving around us. So we're going to try to see that static electricity. We're going to try to see what we can do with them because when we actually want to use it, that's when we make electricity. That's when we make a circuit. We give it a path to go.

[00:04:47]Like when we did with the circle right here, we gave it a path to go. All right. So >> I thought there's one here. You got one.

[00:04:56]Okay.

[00:04:58]>> All right. So, what I have here is a plastic rock. So, what we noticed from before is um doesn't really have any charge to it. So, I'm going to create a charge. What I'm going to use is I'm going to use this cloth. It's kind of has an abrasive to it. Basically, as I'm rubbing here, it's disturbing the electron. So, it'll change the charge of of this this uh pipe.

[00:05:31]All right.

[00:05:33]It actually makes a noise. Those little electrons are going like All right. So, do you think I can move that use this rod and move this key without touching it?

[00:05:50]I can roll it across the board.

[00:05:53]>> All right. So, let's make those electrons. They're talking.

[00:05:57]>> All right.

[00:06:03]That's >> so what's happening is the electrons either that missing from here or on the can on here are going to balance and so they're trying to find each other or stay away from each other.

[00:06:21]All right. So >> really wish YouTube would allow me to adjust >> paper towel >> setting. You get to move this.

[00:06:29]>> Hey dinosaur noob. It's a good day. It's a dry day today.

[00:06:34]>> No thunderstorms.

[00:06:42]>> All right.

[00:06:55]So cool.

[00:06:57]>> All right. So, what are some observations? Did it move or not move?

[00:07:01]>> All right. So, it did move. So, there is some movement of electrons. Did it flow as much as the can?

[00:07:10]>> Probably not. And that's because this is probably not as good in the conductor, but it still was enough that you're moving enough electrons that are moving it around.

[00:07:20]All right. All right. Excellent. So, we saw how that worked, but we can do it with even a little more power. You guys ever seen one of these things? So, this is called a man generator. That is basically the same thing with a lot more energy. So, we're going to take it over here, put it where you guys can see it.

[00:07:50]>> Electricity in my pocket. All right.

[00:07:53]So, the way this works is in this blue base here is a motor. And that motor when I turn it on is going to spin this black belt in this tube here that you can see. On the top and bottom are little cylinders that act like little cones. And they actually scrape off the electrons giving this whole dome a charge just like they're charged up the pipe. Right? And this time the dome is going to get all charged up. So, let's see what happens. We got the electrons all in there. Let's see what happens when we give those electrons somewhere to go. We've got another lab assistant here. This guy we call what do you call him, Ben? He's got a lot of names. I call him Shaggy. [laughter] >> I don't I don't know if we have We have a name for him.

[00:08:40]>> He's been around a long time as you can see. He's been a lab assistant. He kind of needs a haircut. You can see that.

[00:08:46]>> Missing a lower jaw.

[00:08:47]>> Missing a lower jaw of his body.

[00:08:50]>> But he's always here. So, we're gonna give them a little I'll see what happens.

[00:08:57]>> All right. So, what's going on with bins here?

[00:09:02]Feel that myself.

[00:09:05]Okay. So, we said that the dome takes on a negative charge. All those electrons are in there. Well, now we've given them a path. And you guys know what happens.

[00:09:14]Play with magnets, things like that. You know what happens when you get a like a positive and a positive together or a negative and a negative together versus a positive and a negative. What happens when you get a negative and a negative?

[00:09:28]>> Repel. Right. You see any repelling going on there?

[00:09:32]>> Yeah. Every piece of his hair is repelling against each other. They've all picked up that charge from the dome.

[00:09:40]So bring his mirror down back and forth.

[00:09:46]calm it all down. Okay. And we can show you that in another way with some pie pans. So, if we stack a bunch of pie pans on top of here, we can see what that does. Here we go.

[00:10:11]>> Thank you.

[00:10:16]Okay. So, what happened there? We had the pie pans, right? The dome got up, got that negative charge on there. What happened to each pipe pan? They took on that negative charge, right? Negative, repelled to negative, repelled to negative until they were all blown off.

[00:10:31]Well, what happens if we don't put anything on top, but we just bring our discharge one. So, what this does, it just takes the charge out. It gives the electrons a path. goes through this all the way to the ground to the earth which is where they want to go. But I'm not going to do that. I'm just going to bring this close and we will see what that that does back on again.

[00:10:55]Now we can see something visibly.

[00:10:59]You guys see anything?

[00:11:02]>> Yeah. What does it look like?

[00:11:04]>> I like the word.

[00:11:06]>> Money. Yes.

[00:11:09]>> It looks like It's a relaxer charge.

[00:11:14]>> Yeah, it looks like lightning because you know what?

[00:11:16]>> Back and forth.

[00:11:17]>> It actually is. It's called plasma. And we're going to tell you a little bit about plasma next. Ben's going to come out here and help me. So, has anybody played with one of these before?

[00:11:32]>> Oh, actually, actually, I won't come to you guys. [laughter] I bet to hold it. Okay. So, this is called a plasma ball. And this is a a little invention that's based on an invention by this man. You guys read his name?

[00:11:51]>> Do you know about him or do you recognize that last name?

[00:11:56]>> Tesla. What? How do we know Tesla?

[00:12:03]>> Yes. But Tesla are cars around nowadays, aren't they? Electric cars. Yeah. Um, he didn't invent the cars. They were named after him, but he was an amazing scientist. We have a lot of inventions that we have today. But some people thought he's a little bit of a mad scientist because that was his laboratory.

[00:12:22]>> Look at that. You see it?

[00:12:26]>> That is Mr. Tesla's laboratory.

[00:12:31]Got it.

[00:12:33]>> So, we're going to do that next. No, we're not. [laughter] But Mr. Tesla invented something that is inside this little plasma ball and that's called the Tesla coil. Now his was really big but we've got a little small one inside here and that's the bar that you see in the middle there where all the colored streamers are coming from. Okay, that's a Tesla coil. And also inside that dome are special gases and we call those noble gases. You may already know those. So after we finish here, you can take a quick walk over to our periodic table of stuff over there and you'll see the noble gases in the far right hand column in the very top right hand column. I know you guys know this noble gas because you use it on your birthday in your balloons that are floating. What gas is that?

[00:13:22]>> Helium.

[00:13:22]>> Helium. Exactly. You know a noble gas.

[00:13:25]The one underneath there you can see all around us and you're saying lights.

[00:13:31]Neon. Yeah. Neon lights. to go storage.

[00:13:33]You see the open side? That's neon.

[00:13:36]Well, there's a few more noble gases.

[00:13:38]So, when we take them, we put them inside this dome, suck out the air, right? The gases in there, and you get that Tesla coil coil going. That's what you get. You know what that's called?

[00:13:50]Anybody know?

[00:13:50]>> Plasma.

[00:13:51]>> Plasma. The same thing we just saw here.

[00:13:54]So, the cool thing is, if you've never played with one, you take your finger, one finger, and you run it around.

[00:14:01]It follows your finger. Let's do that with just a couple of kids. Let's just take it out and show it.

[00:14:07]>> Yeah.

[00:14:09]>> Very cool.

[00:14:12]>> So, while Ben does that, I'll tell you a little bit about plasma.

[00:14:18]>> So, who knows the three states of matter?

[00:14:21]>> Yeah.

[00:14:24]>> Solid, liquid, gas.

[00:14:25]>> Yes, sir. Do you know the void state of matter? Yes.

[00:14:29]>> He just said it. Plasma is the fourth state of matter. Yes, it is. And plasma makes up more than 99% of our visible universe.

[00:14:42]>> Wait, what did I just say?

[00:14:44]>> More than 99% of our visible universe.

[00:14:47]Where is it? I don't see the plasma. You see the plasma besides >> there?

[00:14:53]>> Oh, I said universe. Our visible universe is huge. Okay. So, where do we find plasma?

[00:15:02]>> In the stars. Yeah. How about our sun?

[00:15:05]>> Our sun is a star. Yes. So, that's our plasma ball. All right. So, we're going to move along.

[00:15:18]>> Yeah.

[00:15:31]Okay. Um, how about we switch over?

[00:15:36]>> Okay.

[00:15:38]>> So, I'll let you do the Orbeez.

[00:15:42]>> Ben's gonna talk about Orbeez.

[00:15:47]>> Let me get you Let me get you a uh a laser.

[00:15:50]>> Oh.

[00:15:56]might need to jump in here.

[00:15:57]>> Okay, that's fine. Okay, so >> I'm a diplomat >> inventor. These things are were invented beyond past my time.

[00:16:05]>> That is true. It disaster time. So, >> but obstacle optics were water fence things.

[00:16:11]>> That is true. That is right.

[00:16:13]>> So, has anybody ever played with these Orbeez?

[00:16:15]>> You kids?

[00:16:16]>> Yeah. Cool. So, do you know what they're made of? They're little squishy water beads. Basically, they're almost all water. Go over 99% water. And they're in a substance on the outside called polymer. Lots of stuff made of polymers.

[00:16:30]What's cool about them is you can take a take a laser light.

[00:16:38]Get it going there. Might need another one. Yep. I think there's one out here.

[00:16:45]We've had toys out all day. So, here we go.

[00:16:49]Yeah, I got one. Okay. So, you see the light? What's happening there?

[00:16:53]>> It's reflecting all around.

[00:16:55]>> Yeah, that's cool because there's space in between the Orbeez. The air is there.

[00:16:59]So, you have two different materials and the light is bending all around each of those orbeez, giving us a nice little light show. But watch what happens to that property when you pour water in it.

[00:17:15]>> Where' the orbeez go? Look at that. They pretty much disappeared, didn't they?

[00:17:21]And watch the light now.

[00:17:24]Straight through. No more refraction.

[00:17:26]Cuz now we just see something that's almost like a solid. It's the water that we poured in there has filled up the space in between the Orbeez. So it's water and water.

[00:17:38]Okay. So next we're going to do Oh, we have to set up. We'll do the balloon. You want to do the balloon?

[00:17:52]All right. So, >> you want to do wind?

[00:17:56]>> Okay, Ben, you win. I'll do >> So, I'm going to switch back to electricity for a moment. And like we said that the electrons are moving around but it doesn't work to actually do anything except for giving us a charge. Doesn't make it allow us to turn on lights use actually use electricity until we make it put it take a copper wire and a magnet. And so instead of using like this machine or I was like wiping around to move the electrons around, what's going on here is I'm going to be turning a copper wire, which copper wire has electrons in it, within a magnet, I'll put it the right way, and it will generate electricity. And the way we can see that we've generated electricity is because we've connected it to a wire and we've connected it to a light. So you see no movement, no electricity.

[00:19:04]>> If I start cranking it like plugging in over here, moving the electrons, I'm giving the electrons a path to go and I'm turning on the light.

[00:19:16]The faster I go, the stronger the light.

[00:19:19]If I had two, I'd have to go even faster. And that's how we get all the lights. So who's doing all the turning?

[00:19:31]Well, I'm not because that would be a lot of work. So, what we have is we have gener we have uh turbines that basically create this where we're using either natural gas, coal, wind, water, something to make to do the turning to generate our electricity. And that's how we get our electricity because if ne if it's not turning no lights we're turning lights.

[00:20:05]All right. So >> All right. So >> So here what I have is I have a little wind turbine and what I'm going to use is I'm going to use wind to to turn this inside here is what I have here a magnet copper m copper and a magnet and it's going to turn and it's going to turn on the light.

[00:20:45]So these are set up so they're supposed to be like blow but you have to blow really hard. So, see if I can do it first and then we'll use the uh other electricity.

[00:21:03]>> All right. So, you see you need a lot of movement to move it around to turn on even just this little light. So, that's how we have our Andy >> wind >> wind.

[00:21:18]And There we go.

[00:21:25]>> You see it?

[00:21:29]>> And what happens when the wing goes off?

[00:21:40]on that because that's a really important thing about our power grid and electricity is that when we generate it, we have to use it or we have to do something with it, convert it into a battery or something chemical to store it so it can be used later. And that's why there's a a difference of when you turn on your switch, you want to make sure that there's enough energy coming that it's going to it's going to come through. not going to wait till oh you know what the turbines are off you get like five more hours of dark and then we'll turn back on the power so gives you lots of stuff to think about in Houston because it used to be just you know hurricane season you know should I have a generator this kind of thing but we have freezes here too so it's having the energy when we need it um generating it and actually being able to use it or store it is all part and there's lots more about that upstairs in the energy hall and about the whole grid. But that's an important part is when you create it, electrons have to be used.

[00:22:44]>> Okay. Excellent. Thank you, Ben. Okay.

[00:22:48]So, we're going to do a little fun game here. A little bit of chemistry. Okay.

[00:22:55]So, we've got I need a little beaker of water. We've got three cups here.

[00:23:02]And I'm going to put just some water in just one of them.

[00:23:10]Okay.

[00:23:13]>> Let's see. A random cup.

[00:23:19]>> Yeah, that ought to work.

[00:23:23]>> All right. So, you've seen the shell game before.

[00:23:32]>> Which one has the water? Were you guys watching closely?

[00:23:37]Yeah, >> the middle.

[00:23:40]>> How about we try that one? We'll see if it's the middle.

[00:23:44]>> Okay.

[00:23:46]>> Look at [laughter] that right behind him. Watch out for this guy.

[00:23:57]>> This one.

[00:23:59]>> Oh, you're good. You are so good.

[00:24:03]Let me see you. Sh.

[00:24:06]>> Where's the water? You saw it in there, didn't she? Where did it go? We got three cups and no water. But you saw me pour it in there, right? Where did it go? Well, let's see. Oh, I feel something. Take a finger like that. Just touch it. Tell me what you feel.

[00:24:29]You feel it? Okay. What did you feel?

[00:24:36]a gel, soft and squishy like gel because it is. I kind of tricked you. There was a powder in there before we started and it's called a polymer. The same thing we talked about with the right polymer again everywhere. As soon as I poured that water in there, sucked up that water and turned it totally solid. And do you know what? All you little ones, you have worn this stuff when you were a baby.

[00:25:06]>> How is that possible?

[00:25:07]>> How did you wear it as a baby?

[00:25:10]>> Do you have an answer?

[00:25:12]>> It's okay. Your parents will have to do it at some point, too. [laughter] >> What else did I do?

[00:25:27]>> All right, we got one more polymer.

[00:25:35]diaper.

[00:25:38]>> Okay, Ben, are you good at blowing up balloons?

[00:25:40]>> No. No.

[00:25:59]>> Tie. Yeah, please. Thank you.

[00:26:08]>> You're good, man. Thank you.

[00:26:09]>> Yeah. Well, you know, 250 years of birthdays.

[00:26:13]>> Okay. So, who thinks I can pierce this balloon with this skewer? It's pointy, right? You think I can pierce it through without a popping?

[00:26:23]>> You think so?

[00:26:25]>> Okay, we're going to give it a try. I'm about a 99. I'm about up to 99.3 success rate.

[00:26:34]>> Gonna go in. [laughter] >> Look, look, look, look.

[00:26:41]>> Working on it. Ben blew it up pretty good here. He's giving me a test. Okay.

[00:26:54]Yeah.

[00:26:59]>> There we go. We got it.

[00:27:01]>> How can we do that? How can you pierce a balloon and it knock?

[00:27:05]>> I know.

[00:27:06]>> Yeah. Tell us.

[00:27:07]>> Because the wood blows the balloon.

[00:27:10]>> The wood blows the balloon.

[00:27:13]>> Whoa.

[00:27:13]>> Closes. Closes the balloon. Okay. Okay.

[00:27:17]>> That's a really good answer. I like it.

[00:27:19]Well, you know what? We keep talking about these polymers. Polymers. Polymer.

[00:27:23]>> We got another one. This is latex is another kind of polymer. And a polymer is kind of like a spaghetti chain.

[00:27:29]Stretches, especially in thick places.

[00:27:32]So in the thick part of the balloon, it can stretch enough to let that skewer go through and I can pull it out. It'll eventually go flat because it's got holes in it, right? But if I was to go into this part where it stretched a whole lot, what's going to happen?

[00:27:50]>> Immediately. Oh my goodness. So, now we told you a little bit about polymers.

[00:27:55]They're really cool. We use them a lot and they can be a lot of fun.

[00:27:59]>> Okay, then what have we got left? I think we have u we can do uh we can do principal and then maybe angular momentum. Look at how >> she gets to experience.

[00:28:22]>> Okay, we're going to swap off here. So, >> we're going to use our hair dryer here.

[00:28:28]>> Oh gosh. You know what? We're pretty short on time.

[00:28:33]>> Yeah, we got we got 10. So, we'll just do these quick quick quick ones and then we will end our great demo day.

[00:28:43]>> You guys had a good day here?

[00:28:45]>> Y, >> right? Awesome. I know some of you Wow, you've been with us a lot. You've seen a lot of demos today, haven't you? That's awesome. I love it. We're going to try to do this pretty regularly, so we'll have more people doing it. Very soon.

[00:28:59]Okay, so this one, you can do this easily at home. All you need is a hair dryer and a pingpong ball. So, I'm going to give it to Ben. And Ben, could you put it on cool in full blast?

[00:29:13]>> Okay, we're gonna put the ping pong ball in the stream of air.

[00:29:20]>> Okay, you can move it up here.

[00:29:23]All right, come back.

[00:29:26]Tilt it just slightly. Yeah.

[00:29:39]>> So Ben has really got that ball spinning, right? Well, that's pretty cool. But why isn't that ball blowing off the people who just push with that with that mirror bladder? Well, we've got another sign. Hey, >> did you say Bernie?

[00:29:55]>> Yes, >> you did. That's his name. This is our scientist who can tell us about this. He studied Beni. You can tell he lived a long time ago. So kind of kind of like mine. He looks like he has a red. So So Mr. Bulli taught us all kinds of things about fluid dynamics. And that means how things move. That's air, water, and even blood. How that moves around. And he said, "If you've got fast moving air, like it's coming out of that hair dryer there, right? It's a stream of air and it's moving really fast. It has low pressure. But outside of that stream, regular old air out here, it's higher pressure. So you got two pressures pushing on that little ball, right? So just holding it right there.

[00:30:43]Just keeping it in this little pocket.

[00:30:46]Well, you know what that pocket?

[00:30:50]You know what that You know what that teaches us, strangely enough? How airplanes lift off the ground? What does that have to do with it? Well, who else's been on an airplane? Yeah.

[00:31:02]You like flying? Yeah. Well, let's pretend like I'm taking a ride. I'm on a plane. I'm on my seat and this is my airplane wing. Okay. Hold it up like that. All right. So, I'm sitting here and we're about to take off and the pilot says, "Okay, folks. We're ready for takeoff." and we start going down the runway. What is going to happen to that air when it hits this wing right here, right? We're going to air on top, air on bottom.

[00:31:31]Sounding kind of like the haird dryer.

[00:31:32]We got two air, two kinds of air going.

[00:31:35]A little faster here, which is lower pressure. A little slower air here, comparatively higher pressure. Two pressures again. They're pushing on that wing and we're accelerating. What's going to happen, kids? What's it doing?

[00:31:50]>> Lift it off. Yeah, lift it off. That is called Bernie's principle. Things like that happen. And you can do this yourself. You can prove it to yourself.

[00:32:00]You might have done it before with your parents permission. Put your arm outside your car window when you're going into a neighborhood about 25 or 30 miles an hour. Do like an airplane wing and watch what happens to your arm. What do you think it's going to do?

[00:32:16]>> Yeah. It's going to be pushed up just like that. It's gonna want to lift up and that's for his principal. Now you can go. You know that you can impress your friends with it. Okay, Ben, take it away.

[00:32:28]>> Uh, well, >> yeah, that's all right. I guess I guess we'll close out with this. Okay, we have one more thing just to show you guys real quick. It's just a fun one.

[00:32:38]>> Okay, Ben, do you want to get on it or do you want to >> You can get on it.

[00:32:42]>> Okay.

[00:32:44]>> Okay. You give me you be my spinner then.

[00:32:47]>> Okay.

[00:32:49]>> So, we're going to get on here. Ben's going to give me a good spin with his bicycle.

[00:32:56]Not me. Not me. The bicycle wheel.

[00:33:00][laughter] I got a big boy.

[00:33:02]>> Okay. Okay. Spin it really, really, really hard. As hard as you can. Yeah.

[00:33:07]Give it another. Awesome. Okay. So you can see what happens when I turn this wheel. It is turning me to keep all of these vectors. The forces balanced.

[00:33:22]Sorry about the mic there. Let's do it one more time. Give it a really hard spin. So what this is called and what it's showing is called the conservation of angular momentum. There's all kinds of forces going on there.

[00:33:36]I said called vectors. Yeah.

[00:33:40]And as long as I keep spinning, it keeps trying to balance me with it.

[00:33:49]Similar to when you're on your bike and I'm on a turntable here and it's turning back and forth. So what's the real world application of that? Well, it's up above us. Up in space, we use gyroscopes on satellites and the International Space Station even uses it. And when they use things like this gyroscopes, they can change direction going back and forth without having to use any fuel. Just using that principle to go back and forth. So, I think that's about it for us. Thank you so much, folks, for coming out today. We had a great demo day. We hope you come back and see us anytime.

[00:34:27]>> Thanks, y'all. I'm turning my microphone back on.

[00:34:30]>> I'll put it on the pendulum just for a minute while I close up the stream here.

[00:34:35]Now, a pen uh a peg fell a few minutes ago, so it's probably not gonna fall again.

[00:34:42]Maybe it will while I'm streaming. I'm gonna go collect the other microphone.

[00:34:47]Um yeah, like she said, I don't know if you could hear. Uh this stream was a little bit of an experiment, a little technical experiment on my end. Hi, I'm the YouTube manager here. Uh but I hope you enjoyed it while I figured out kind of audio and what kind of cameras I might want to use next. But let me go grab the other microphone and let you keep watching the pendulum. Uh, while I do that, maybe I'll keep talking to you.

[00:35:10]So, I hope you all enjoyed that. We're here, of course, at the Houston Museum of Natural Science and we plan to do more lives cuz that was that was really fun. Oh, a peg fell.

[00:35:25]What an awesome end to the stream is seeing a peg fall. Did you all see that?

[00:35:30]That was kind of sick. Maybe you didn't see it. Maybe it was kind of far away.

[00:35:33]You'll have to zoom in.

[00:35:36]It's funny. You never know how it's going to work out. I'll let you all know just really quick um while we close out the stream here that if y'all have ever come to the museum and you sit here and you watch the pendulum and you've been just waiting for a peg to fall and it seems like they're never going to fall. Some people have been coming to the museum for, you know, 20 years and they've never seen a peg fall. So, I'm here to tell you once and for all how often a peg falls around the pendulum. So, per peg, if you were going on that side of the pendulum and it's going around and knocking over the pegs throughout the day, between each peg on one side, it's give or take about 45 minutes, give or take, I'd say between 45 and 50 minutes. Uh the pegs are made by hand. The ring is made by hand. So there's little millimeter differences between pegs and that adds up to a few minutes at a time. But on average, it's about 45 minutes between this peg, that peg, this peg, that peg.

[00:36:31]But you see there's pegs on either side.

[00:36:33]So you've got to divide that 45 to 50 minutes to, you know, between 20 25 minutes, maybe 27 minutes uh between pegs. I would say it's closer to 20 25 minutes. So that is the window of being able to observe a peg fall. It is officially around 25 minutes or so. So, if you just walk up to the pendulum, the longest you'll ever wait to see a peg fall is about 25 minutes. Some of y'all are just really lucky and you walk up and you're in that last minute and you see the the peg fall and you're super lucky about that.

[00:37:06]>> You're over I'm doing the live stream over here to the YouTube channel.

[00:37:08]Question. Yeah. What's up?

[00:37:09]>> Um, yeah. I was trying to explain to my friend why it goes around a circle, but I didn't think I did a very good job of it. I'm sure you you seen.

[00:37:16]>> So, yeah, I'm we're doing a >> Yeah. So, I just made some videos about the the pendulum. I'm the YouTube manager for the museum and the podcast also. So, the Earth is rotating underneath the pendulum. The pendulum only goes in a straight line forever. No matter how you you bring it back, whatever direction you pull it, it's going to go away from you and it's going to maintain that straight path forever and ever. It's the Earth that rotates underneath it. That's what a fukco pendulum is designed to uh demonstrate.

[00:37:46]So at the north pole, it would knock over pegs through a 24-hour period. All these pegs would be knocked over. At the equator, since it's only going in a straight line, it would only go in a straight line. It knock over one peg and there no more pegs for the day. It would not appear to precess around at all. So at the North Pole, lots of pegs get knocked over. On the equator, no pegs, just straight line forever. Houston is about 30° north of the equator. So that's why it takes us about 2 days to go around the full perimeter or for the technically speaking the earth to go underneath it every 48 hours. The way it keeps moving um the earth rotation has nothing to do with keeping the pendulum moving. A lot of people kind of uh that's kind of mis I don't know misinformation or whatever uh confusion. Up in the top we have a it's an electro ring magnet >> that throws people off. That's like oh my goodness. See it doesn't it's all it's all bunk or whatever. That ring magnet is not applying any directional force. It's not like saying hey keep going this way. All it is is to maintain that momentum. Otherwise somebody would have to sit here and every few hours give it a little nudge. And back in the day that's kind of how they would do it.

[00:39:04]Um, but this has a little electromagnet that trips a little light circuit like your bathroom nightlight. Triggers that magnet to come on just for a moment to maintain this momentum without busting through the glass. You know, it's not adding anything and that's how it stays moving. But >> does >> original question orbit affect at all or just the rotational?

[00:39:26]>> It's just the location on the earth. It is not. Um so the tilt of the earth in seasons like summer and winter that does not affect uh the precession at all.

[00:39:35]It's just where it physically is in relation to the north pole and the equator and on the bot you know obviously in the south southern hemisphere it would appear to precess the other way around. It's the reason why hurricanes spin uh counterclockwise up here and typhoons spin clockwise in the south pole. So that would from our perspective, it's crazy cuz pendulums are so beautiful and like so like zen.

[00:40:02]>> Yeah.

[00:40:03]>> But the physics underneath it is like >> you get lost in it. Like it's crazy. I still get lost in it.

[00:40:09]>> Yeah, for sure. Of course.

[00:40:10]>> So it's I understand how the pendulum moves and uh >> Yeah.

[00:40:14]>> or doesn't move when Earth moves, right?

[00:40:16]How do you set up?

[00:40:18]>> How do you set it up in the first place so it doesn't have that same relative motion that the Earth's rotation has?

[00:40:25]>> So the momentum it's like inertia. Inertia you don't nothing will change direction unless I'm going to push your shoulder a little bit will kind of change your direction. So once you pull it back it wants to go straight forever unless there's something outside like the earth. People think that since the earth rotates, it would twist the cable with it. That is technically very minutely true. Ours is decoupled. It's a ball bearing in the top. So, it's decoupled from the earth itself.

[00:40:56]>> Also, just the very nature of how thin that cable is. And the point of attachment is so small up there that the mass of the of the bob or the plum, whatever you want to call it, which is 81 kg. It's like 170 something pounds or whatever. That mass being heavy counteracts the little force up there, the torsion, the twist force. So >> I see >> it'll it'll only go. So if you started it like this direction, it would stay that direction. It's decoupled. So the the earth's rotation will not twist along with the the cable.

[00:41:30]And even if we didn't have the magnet to keep it just maintain the momentum, it would swing long enough to demonstrate the exact same principle. So other pendulums that that aren't um uh don't have the little nudge at the top, those pegs are a lot closer to the center because if you release it and let it go, it takes a few hours, but that swing will get narrower and narrower and narrower. So you'd want the pegs closer to the center to, you know, over the course of two hours knock over as many pegs as possible to demonstrate the principle. So that's all this thing is.

[00:42:04]The Fukco pendulum is just demonstrating a principle of the Earth rotating under it. Very cool.

[00:42:11]>> Before GPS and satellites, that's how navigators figure it out. They do the pendulum. And if it was going straight line all day, okay, we're at the equator.

[00:42:20]>> Really?

[00:42:21]>> Yep. It's if they go up to the north, further north, okay, it precessed a little bit around the perimeter, so we must be that many degrees north. And if it went the other direction, we must be that many degrees south. So, it's really cool.

[00:42:37]>> Pegs are set up by hand every morning by a person.

[00:42:41]>> That's awesome.

[00:42:42]>> And they're all handmade.

[00:42:45]>> Yeah.

[00:42:45]>> Thank you so much.

[00:42:46]>> Of course.

[00:42:46]>> Yeah. We got We just saw one fall over, so that was cool.

[00:42:49]>> I know y'all are lucky. Have you been here before or like >> So, but you you say you've been here before. Have you ever seen a peg fall?

[00:42:56]>> I've seen two or three in my life. I've seen this one before. I've never seen a peg knock before. See, people like they see pendulums their whole life and some never do it. Some people just walk up their first time.

[00:43:07]>> Oh, hooray. And it it's like, "Oh, man.

[00:43:10]I've been waiting forever. You saw it the first time."

[00:43:13]>> Um, yeah. So, that's how the pendulum works. The scratches on the bottom. I don't want to keep your time, but >> Oh, we're nervous.

[00:43:22]>> Back this was installed in the early '7s.

[00:43:24]>> Okay. And the first cable used was just a regular, you know, uh, steel cable.

[00:43:31]>> Turns out steel over that distance, cuz the steel has its own weight in the bob, it stretched. So, very gradually, the first few months or years that we had it back in the 70s, like why is it scraping the bottom? We replace the cable with aircraft. Are we closing?

[00:43:46]>> Yeah.

[00:43:47]>> Okay. So, that's a good that's a good cue. So, I'm going to end the live stream, y'all.

[00:43:52]I like to Yeah, >> of course. So, I walk out, they're going to kick me out, too, even though I work here.