Speaker 1: Get in touch with technology with tex Stuff from dot
Speaker 1: com and welcome to tex Stuff. I'm Jonathan Strickland and
Speaker 1: today I am joined in the studio by Mr Joe McCormick.
Speaker 1: Hi Joe, Hi there everybody. How are you doing, Joe?
Speaker 1: I'm doing just fine today. I've enjoyed a nice lunch
Speaker 1: that we had provided for use in the office today. Yes,
Speaker 1: we we ate too many tatos to this day. Yeah,
Speaker 1: talk to things past, but today we're going to talk
Speaker 1: about things way past. We're talking about some of the
Speaker 1: earliest machines ever, the simplest machines. And this is due
Speaker 1: to a little listener mail. Now. This comes to us
Speaker 1: from Kyle via Facebook, and Kyle wrote, have you all
Speaker 1: ever done a podcast on the six classical simple machines?
Speaker 1: If not, that might make for an interesting topic. Oh
Speaker 1: I remember these from school? I do too, is accept
Speaker 1: I don't remember them? What were they? There was the toaster,
Speaker 1: there was the what the electric camera? Yeah, I think
Speaker 1: I'm pretty sure the A T M was on their right,
Speaker 1: that's way up there. Yeah, and uh I think uh,
Speaker 1: I think perpetual motion. That was one. It was really simple.
Speaker 1: It just kept going simple and it also know as
Speaker 1: the clock. Yes, yeah, yeah, no, of course, the six
Speaker 1: simple machines are far simpler than that, but they are
Speaker 1: really important. They they form the basis of a lot
Speaker 1: of the machines that we use today, and ultimately, most importantly,
Speaker 1: they make work easier. Work is hard, work is hard.
Speaker 1: Work is hard to explain unless you're a physics teacher
Speaker 1: and you do it all the time. But it has
Speaker 1: been many, many years since I took a course in physics,
Speaker 1: and while I still understand and appreciate simple machines and
Speaker 1: the concepts of work and force and this sort of thing,
Speaker 1: it behooved me to do a quick refresher course before
Speaker 1: doing this podcast. We'll share your knowledge with us. Jonathan,
Speaker 1: all right, So work is force acting on an object
Speaker 1: in the direction of motion. Uh. And so you could
Speaker 1: think of it in the equation of force times distance
Speaker 1: equals work. All right. Uh. So this is why we
Speaker 1: we express work in units of force and time, such
Speaker 1: as a Newton meter and a newton. Since this raises
Speaker 1: the next question, a Newton is the amount of force
Speaker 1: required to accelerate one of mass at one per second squared.
Speaker 1: So these are the basic units we're talking about, although
Speaker 1: we'll also be talking about pound foot as a means
Speaker 1: of unit of measurement because we're in America and we
Speaker 1: use antiquated systems of units in our measurements, then we
Speaker 1: can't understand how to use this funky you know, metric
Speaker 1: system approach or or the standard unit approach. Okay, but
Speaker 1: wait a second, how is work different from force? So
Speaker 1: force is an agent that results in accelerating or deforming
Speaker 1: an object. So if you want to get an object
Speaker 1: to start moving, you have to apply force to it.
Speaker 1: If you want to punch a hole in a wall,
Speaker 1: you have to apply force to it. But work is
Speaker 1: the force acting on that object in the direction of motion.
Speaker 1: So it's it's it's a it's it encompasses more than
Speaker 1: just the force. Okay. So if I pushed a wheelbarrow
Speaker 1: twenty ft over a certain period of time, that would
Speaker 1: be work, right, But your actual pushing against the wheelbarrow
Speaker 1: itself its force. So you know, it's it's kind of
Speaker 1: a perspective thing in a way. But it's very important
Speaker 1: when you start talking about how much how much work
Speaker 1: and actual task is versus the amount of force that
Speaker 1: you have to do to accomplish that task. Okay, and
Speaker 1: so machines in the simplest way, are something that helps
Speaker 1: us do work easier. Right, Yeah, so that we either
Speaker 1: have to do the work with less force or uh really,
Speaker 1: machines can change the dynamics of force and distance in
Speaker 1: interesting ways, and sometimes it's ways that might seem counterintuitive
Speaker 1: to you. Will definitely talk about something that seems counterintuitive,
Speaker 1: at least the fort when I first thought of it, it
Speaker 1: it was counterintuitive when we get to h levers, which
Speaker 1: spoiler alert are actually one of the six. But at
Speaker 1: any rate, Yeah, it means that we don't have to
Speaker 1: exert as much energy when we are trying to accomplish
Speaker 1: this task, the specific type of work, whatever that might be.
Speaker 1: And that was really important. I mean, obviously in early,
Speaker 1: the earlier days of humanity, you know, we spent most
Speaker 1: of our effort just trying to make sure we weren't dying,
Speaker 1: and anything that would save us that kind of effort
Speaker 1: meant that we could we could reserve more energy for
Speaker 1: very important things like running away. It's a big one. Yeah,
Speaker 1: but then you rate. So there are four main ways
Speaker 1: that machines make work easier, and the first is that
Speaker 1: he can increase the magnitude of a force, so they
Speaker 1: essentially amplify the amount of force being applied to an
Speaker 1: object or system. So you are are exerting a certain
Speaker 1: force upon a machine, the machine amplifies that force applied
Speaker 1: to whatever the load is. That's usually what we call
Speaker 1: the the thing that you're having the machine act upon,
Speaker 1: and it amplifies that force so that the load is
Speaker 1: is experiencing more force being exerted upon it than you
Speaker 1: are putting into the machine. Okay, so in early humanity terms,
Speaker 1: you might think of this as something like an ax right, yeah,
Speaker 1: that would be one, uh you know, any or a ramp,
Speaker 1: just a simple ramp, because you would you would be
Speaker 1: exerting less force to move the object as if you wanted,
Speaker 1: let's say you wanted to move an object, uh to
Speaker 1: a allege that's ten ft above ground hole and if
Speaker 1: you were to actually just lift that object physically, it
Speaker 1: would require a certain amount of force on your side.
Speaker 1: But if you used a ramp, it would decrease, especially
Speaker 1: a very long, gradually sloped ramp, it would decrease the
Speaker 1: amount of force you needed to get the thing moving.
Speaker 1: It would just increase the amount of distance you would
Speaker 1: have to travel to get it to where it needs
Speaker 1: to go. We'll talk more about that in a bit.
Speaker 1: Oh yeah, well, I guess an ax would actually involve
Speaker 1: more than one kind of simple machine because it has
Speaker 1: an inclined plane or a wedge on it. Yeah, I
Speaker 1: thought so, maybe what I should have said would be
Speaker 1: a club, a club that would magnify force, right, Yeah. Yeah.
Speaker 1: There's also the the idea of transferring a force from
Speaker 1: one place to another. Machines that allow us to apply
Speaker 1: a force in one place the forces transferred to another place.
Speaker 1: So uh, this can be uh, we'll get into some
Speaker 1: examples a little bit later. There's also changing the direction
Speaker 1: of the force, where you may have to apply a
Speaker 1: force in one direction and it's being exerted in another
Speaker 1: classic example this would be a lever or a pulley
Speaker 1: where you know the classic lever where I might like it.
Speaker 1: With a classic leaver, I pushed down on one side,
Speaker 1: the other side goes up, so I'm actually pushing the
Speaker 1: opposite direction of where the force is being applied. Yeah.
Speaker 1: Then there's also the increasing the distance or speed of
Speaker 1: a force, which is a pretty simple concept. Uh. And
Speaker 1: this is the one that to me was the most counterintuitive.
Speaker 1: When we get to leavers, but I want to save
Speaker 1: that for when we get there. And of course, a
Speaker 1: combination of machines can create a wide array of effects.
Speaker 1: And we'll talk about some compound machines, which are uh,
Speaker 1: you know, it's obviously two or more simple machines put
Speaker 1: together to make something more complex. Okay, well, one of
Speaker 1: these simple machines has got to be the wheel, right, well,
Speaker 1: the wheel and axle to be to be specific. But yes,
Speaker 1: I guess without an axle, a wheel isn't not as useful,
Speaker 1: no it you know, they're essentially POGs. Yeah, you could
Speaker 1: push it a little bit and then you'd have to
Speaker 1: keep putting it back under the thing. Yeah. In fact,
Speaker 1: that's exactly how early humans were moving large weights. They
Speaker 1: would have a collection of logs and they would lay
Speaker 1: those out on the ground. They place a heavy weight
Speaker 1: on top of the logs. They pushed the heavy weight.
Speaker 1: The heavy weight would roll across the tops of those logs.
Speaker 1: But that would mean that you get closer to the edge, right,
Speaker 1: you're the the end of the object. We get closer
Speaker 1: to the last remaining log in the front. You would
Speaker 1: have to pick up the logs in the back, run around,
Speaker 1: put them down in front of everything. Was not the
Speaker 1: most efficient means of getting a heavy weight from point
Speaker 1: A to point B. I bet that was a fun job. Yeah.
Speaker 1: And now, granted, when all you're trying to do is
Speaker 1: build a megalithic structure to sacrifice humans on. Well, and
Speaker 1: here's the thing. The people who were building said megalithic
Speaker 1: structures often time was not something they were really that
Speaker 1: concerned about. Yeah, but at any rate, Um, if you're
Speaker 1: looking at the wheel and axel, we believe that was
Speaker 1: invented sometime around thirty five hundred BC E. Yeah, the
Speaker 1: earliest evidence actually comes from thirty two hundred from Sumerian artifacts.
Speaker 1: And also it appears to have been independently invented in
Speaker 1: China around d BC. Okay, so not shared from the Sumerians,
Speaker 1: but different people came up with the same idea. Yes,
Speaker 1: that's that seems to be the case. There are some
Speaker 1: people who suggest that no, there was one common ancestor
Speaker 1: for all wheel and axles, and that that then proliferated
Speaker 1: across the rest of the world. But uh, the research
Speaker 1: I read suggested that in fact it did appear independently,
Speaker 1: which is kind of cool. So this allows for obviously
Speaker 1: much easier travel and transportation. Right, it reduces the friction
Speaker 1: that you would experience when you're pushing something against the ground.
Speaker 1: That makes a lot of sense because I can imagine
Speaker 1: one of the most common work problems in the ancient
Speaker 1: world was just getting stuff from one place to another,
Speaker 1: and it probably wasn't all is megalithic structure, materials, you know,
Speaker 1: moving a giant stone, just moving your supplies. You've got
Speaker 1: foods you've collected or foraged, You've got you know, tools
Speaker 1: or building materials you want to take with you. How
Speaker 1: do you get them from one place to another? I mean,
Speaker 1: if all you've got is you can carry them on
Speaker 1: your back, right, you might build a sledge or something
Speaker 1: so that now you have some sort of animal that's
Speaker 1: pulling it. But that's not very efficient. It's very slow going,
Speaker 1: and of course if you hit any terrain that's not
Speaker 1: conducive to such vehicles, then you're really stuck, literally in
Speaker 1: some cases. So yeah, the wheel reduces friction, right, that's
Speaker 1: the big thing it does in this In this use.
Speaker 1: There's another use for the wheel and axle that we'll
Speaker 1: talk about in a second. But when you attach it
Speaker 1: to something like a cart and you have an axle
Speaker 1: and wheel set up there. Then the wheels turning reduces
Speaker 1: the friction that you experience when you're pushing this against
Speaker 1: the ground, and it reduces the amount of force you
Speaker 1: need to use to get this thing moving. Um. It's
Speaker 1: you know, pretty simple concept. And there are two different
Speaker 1: really you know types of wheel and axles. There's the
Speaker 1: type of wheel and axle where the wheel can move
Speaker 1: freely around the axles. The axle remains stationary in respect
Speaker 1: to the wheel. The wheel just rotates around the axle.
Speaker 1: And then there's the fixed that that that one would
Speaker 1: be fixed to the frame of the cart, so the
Speaker 1: axle is fixed and the wheel moved. And then they're
Speaker 1: also the type where the axle turns along with the wheel. Uh.
Speaker 1: And it has to be in some sort of bearing
Speaker 1: that will hold on and allow it this turning motion.
Speaker 1: I'm trying to think what would be the advantages and
Speaker 1: disadvantages of each. So if you have free moving wheels,
Speaker 1: each wheel can move independently, um. But if you have
Speaker 1: wheels attached directly to the axles, then the wheels on
Speaker 1: each end of one axele have to move together, which
Speaker 1: you know, you look at cars. Yeah, you know, if
Speaker 1: if all of our cars had each wheel moving independ
Speaker 1: lian some actually do have some four wheel independent drive. Uh,
Speaker 1: then that's different than if they're all working together in concert,
Speaker 1: if you will, and so, yeah, I mean they're they're
Speaker 1: different use cases and there are different advantages and disadvantages. Uh.
Speaker 1: The important thing to remember is that this simple machine
Speaker 1: is one of the things that helped revolutionize humanity and
Speaker 1: keep humanity alive and allowing it to thrive. Um. Obviously,
Speaker 1: otherwise we just wouldn't get our stuff to where it
Speaker 1: needs to be. It would be tough. Uh. So another
Speaker 1: thing you can do with the wheel and axle besides,
Speaker 1: you know, attach it to a vehicle and have it
Speaker 1: moved through. Uh. The The wheel and axel has a
Speaker 1: multiplying force aspect to it, so the force around the axle.
Speaker 1: Think of the axle is kind of like a small
Speaker 1: cylinder in the center of a larger cylinder, the larger
Speaker 1: one being the wheel and the small one being the axle.
Speaker 1: The rotational force around that small cylinder is greater than
Speaker 1: the rotational force on the outer cylinder, but the distance
Speaker 1: traveled on the outer cylinder is greater than the distance
Speaker 1: traveled in the inner cylinder. Okay, Now, what that means
Speaker 1: for us is that you can use a wheel as
Speaker 1: a means of like a crank or uh, you know,
Speaker 1: a valve, something along those lines, and you can apply
Speaker 1: a small amount of force to the outside of that wheel.
Speaker 1: The force being experienced on the axle part is much greater.
Speaker 1: So if you have something that normally would be fairly
Speaker 1: tough to turn, if you have a large enough wheel,
Speaker 1: it starts to become easier and easier to turn it,
Speaker 1: which is why you start seeing things like those giant
Speaker 1: wheel like um uh handles for things like the heavy
Speaker 1: doors and submarines, things like that. So, yeah, that it
Speaker 1: allows you to move much heavier machinery or gears or
Speaker 1: whatever using a small amount, relatively small amount of rotational
Speaker 1: force on a larger surface, and the multiplication of that
Speaker 1: force is what gives you the ability to do a
Speaker 1: lot of work. Yeah, I can see that. In like, say,
Speaker 1: the at the helm of an old ship, you would
Speaker 1: have a very large wheel. I'm sure it took a
Speaker 1: lot of force to move the rudder of the ships.
Speaker 1: Having a larger wheel probably made it easier. I'm glad
Speaker 1: you brought that up. I'm glad you brought up the
Speaker 1: wheel because or the helm obviously, because that that will
Speaker 1: allow us to talk about some interesting different types of machines,
Speaker 1: not just the wheel, but our next machine, the lever,
Speaker 1: because before the helm, before the wheel of a ship,
Speaker 1: which really didn't come about until the really the late
Speaker 1: eighteenth century. Yeah, yeah, you see those wheels on ships.
Speaker 1: Those are all modern inventions. In the long run, the
Speaker 1: classic way of controlling a ship was with a tiller,
Speaker 1: which was more like a lever. So a tiller is
Speaker 1: essentially it's a it's a lever that comes out, you
Speaker 1: hold onto the end. You make small adjustments on one side,
Speaker 1: but because the way the lever is adjusted, it makes
Speaker 1: larger changes with the rudder of the ship. The helm
Speaker 1: of a ship involves a lot of other parts. It's
Speaker 1: really a compound um machine ultimately, because you've got the wheel,
Speaker 1: you've got some pulley systems that connect the wheel to
Speaker 1: the rudder. It's pretty cool. So I'm glad you brought
Speaker 1: it up. Well, you know, if you look at a
Speaker 1: wheel like that as uh, something that allows you to
Speaker 1: apply force over a greater distance to create more force
Speaker 1: on a shorter distance. In the middle. It's kind of
Speaker 1: like some types of levers, like, for example, a torque wringe. Right,
Speaker 1: So if you if you have a wrench and you
Speaker 1: have a bolt that you know it's really it's really sorry,
Speaker 1: it would be a nut, I guess a nut, and
Speaker 1: it is really hard to loosen. It takes a lot
Speaker 1: of force to do it. You can do it by
Speaker 1: having a longer handle on your wrench. The longer the handle,
Speaker 1: the easier it is to get that thing loosened. Right,
Speaker 1: And you have to travel a greater distance, uh, in
Speaker 1: a circle, in a circle right for you to get
Speaker 1: that that nut to go one complete rotation. But it's
Speaker 1: far easier as far as the amount of force supplied.
Speaker 1: I like that you pronounce it lever and I pronounce
Speaker 1: it lever. It's gonna get really interesting when we're talking
Speaker 1: about leverage. So the data data, Yeah, this is the
Speaker 1: device that gives us a leverage, and which is really
Speaker 1: how I would say it. I don't know why I
Speaker 1: say lever, but then I say leverage. I just don't.
Speaker 1: I guess it's you know, it's just because that song
Speaker 1: you know, fifty Ways to Love your lever. Okay, never mind,
Speaker 1: you love them and then you love them. So remember that,
Speaker 1: Like we were saying, work equals force times distance, and
Speaker 1: like Joe was just pointing out, if you increase the distance,
Speaker 1: that means you you can decrease the amount of force
Speaker 1: to do the same amount of work, right, or you
Speaker 1: could increase the amount of force and decrease the amount
Speaker 1: of distance and get the same amount of work. It's
Speaker 1: those two factors that determine the amount of work that's done.
Speaker 1: So using a lever, we can change that amount of
Speaker 1: force applied. Uh. And the law of the lever proposed
Speaker 1: by Archimedes you may have heard of him, is that
Speaker 1: quote magnitudes are an equilibrium at distances reciprocally proportional to
Speaker 1: their weights. End quote. That clears everything up, but it's
Speaker 1: essentially what we're talking about. So what are the basic
Speaker 1: parts of a lever? You've got, uh, Your the lever
Speaker 1: itself is the side that you apply the force to. Yeah. Yeah,
Speaker 1: And then you've got something that it typically has to
Speaker 1: rest against at some point along the beam. You think
Speaker 1: of the beam as the full length of whatever the
Speaker 1: lever is. The fulcrum is the pivot point that it
Speaker 1: rests against that you you use to help UH apply
Speaker 1: force to whatever the output side is typically speaking, and
Speaker 1: UH the way this works as to spending on what
Speaker 1: side is longer, that's going to travel more distance and
Speaker 1: and apply less force. So if you have a weight
Speaker 1: and you put the short side of a beam under
Speaker 1: that weight, and then you've got a fulcrum there, and
Speaker 1: then the long side of the beam is the one
Speaker 1: that you push down on. You have to push further
Speaker 1: to make the weight go up the distance you wanted
Speaker 1: to go, but you're using less force than you would
Speaker 1: if you were to just lift the weight up bodily
Speaker 1: straight up. So we thought this would be easier to
Speaker 1: understand with an example. So imagine that you've got a
Speaker 1: fifty pound weight. I'm just gonna do a little bit
Speaker 1: of metrics here, just at the beginning, and then I apologize.
Speaker 1: You're just gonna have to use conversions to convert everything
Speaker 1: over because I didn't do it for everything. But if
Speaker 1: you're talking about fifty pounds, that's about twenty two point
Speaker 1: sevens and you want to lift it up two ft,
Speaker 1: which is about point six meters. To do this, you
Speaker 1: have to do a hundred pound feet of work or
Speaker 1: one thirty five point six new meters of work, because
Speaker 1: again it's force times distance, So you'd have the fifty
Speaker 1: pounds of weight times the two feet and that gets
Speaker 1: the hundred pound foot work. Now, if you used a
Speaker 1: lever that was twenty ft long on one side and
Speaker 1: then ten feet on the other side, So so the
Speaker 1: side that you're going to apply force two is twice
Speaker 1: as long, and you've got a fulcrum that's just uh
Speaker 1: that's one ft tall. It would be half the amount
Speaker 1: of force you would need to lift that load than before. Um,
Speaker 1: So it's you know, it's it's much easier. And of
Speaker 1: course if you were to extend the lever longer, it
Speaker 1: would be less and less force, but you have to
Speaker 1: travel greater distances to get it up the two feet
Speaker 1: that you want. This is why you have the famous
Speaker 1: possibly apocryphal quote, uh that our committees said that he said,
Speaker 1: if he had a lever long enough, you could move
Speaker 1: the world. I guess that's probably true. Yeah, I guess, well, no,
Speaker 1: I don't probably using it would depend It would depend
Speaker 1: on what the lever or lever was made of, wouldn't
Speaker 1: it Because as at a certain point when you're trying
Speaker 1: to move things of great enough mass are taking enough
Speaker 1: force to move, you'd reach the breaking point of your lever,
Speaker 1: wouldn't you. Well, yeah, I mean if you had something
Speaker 1: that was that long, unless it had incredible strength, it would, uh,
Speaker 1: it would break under its own weight. Carbon nanotubes. Yeah,
Speaker 1: that's clearly that's how we you know, that's that's a
Speaker 1: forward thinking answer right there. So leavers change the direction
Speaker 1: or they can change the direction of an applied force,
Speaker 1: but depends upon the input and output output forces relative
Speaker 1: to the fulcrum. And there are three classes of levers.
Speaker 1: So the one we just talked about that example, the
Speaker 1: you got the it's it's like the seesaw looking type
Speaker 1: of lever. That's a the first class style of lever. Okay,
Speaker 1: So one side of the seesaw is longer than the
Speaker 1: other side. You can use the longer side to lift
Speaker 1: heavier loads. And it also changes the direction of the
Speaker 1: applied force. That's one of the one of the elements
Speaker 1: of it. The second ass it's more like a wheelbarrow,
Speaker 1: which involves two simple machines. You have the wheel and axle,
Speaker 1: but you also have levers. The handles act as levers. Now,
Speaker 1: in that case, the fulcrumb is on one end of
Speaker 1: the entire beam. Think of the handles as a beam.
Speaker 1: So the fulcrumb in this case, the wheel is weigh
Speaker 1: on one end. Then you have the load, which is
Speaker 1: actually little load that's inside the wheelbarrow. Then you have
Speaker 1: the handles the input that you create. So it's different
Speaker 1: from the seesaw right, where you would have the fulcrum
Speaker 1: in the center. Now you have the fulcrum on the end,
Speaker 1: then the load, and then you lifting it this one
Speaker 1: instead of reversing the direction of the force, it's the
Speaker 1: same direction right, because you're lifting up on a wheelbarrow,
Speaker 1: handles and it and it lifts the load up as well.
Speaker 1: So it's different from uh, the first class of leavers.
Speaker 1: The third class is the one that seems the most
Speaker 1: counterintuitive if you first think about it. So would the
Speaker 1: flat end of a crowbar be a second class lever
Speaker 1: because they're what you're doing is you don't have the
Speaker 1: full crumb in the middle. You're you're pressing the end
Speaker 1: against the inside of the door frame, say, and then
Speaker 1: a little bit further towards the end you're holding is
Speaker 1: what's mashing against the door, and you're using it to
Speaker 1: pry like a prying action seems like second class levers.
Speaker 1: It is, and of course if you were to turn
Speaker 1: the crow bar around to use the curved end be
Speaker 1: a first class just like a Claude hammer would be
Speaker 1: as well. Here's a Claude hammer to remove nails. Uh
Speaker 1: so that's a great example. Third class levers are the
Speaker 1: ones to me that are the most counterintuitive. Um they
Speaker 1: have the fulcrum at one end, then you have the
Speaker 1: input force, then you have the output force. So you
Speaker 1: know when the wheelbarrow example, we've got input force on
Speaker 1: one end, then output in the middle, then the fulcrum
Speaker 1: in this case fulcrum input output and you might think,
Speaker 1: wait a minute, what the how does that even work?
Speaker 1: It doesn't sound like and why would you want to
Speaker 1: use that? Because if you use, if you use this
Speaker 1: sort of lever, it has what we call an ideal
Speaker 1: mechanical advantage of less than one ideal mechanical advantage. This
Speaker 1: is what's telling you how how how much it's helping
Speaker 1: you in the sense of how much force you have
Speaker 1: to apply versus the force that you're getting out of
Speaker 1: This too for the issue of making work right. So
Speaker 1: here you're you're actually at a loss yeah, and you
Speaker 1: might wonder, well, why would you want to do that,
Speaker 1: And the reason is that you are that output forces
Speaker 1: actually applied over a greater distance. So it's kind of
Speaker 1: the reverse of what we were talking about earlier about
Speaker 1: how with the wheel, when you have the greater distance,
Speaker 1: you have to apply less force, but you get more distance.
Speaker 1: In this case, you have to apply more forced down
Speaker 1: at the input, but you're getting greater distance at the output,
Speaker 1: which is really useful if you're up to bat. A
Speaker 1: baseball bat is a third class lever, so this would
Speaker 1: be like my club example earlier exactly, that's essentially a
Speaker 1: third class leaver or a first class bunk on the head.
Speaker 1: Uh So anyway, yeah, very interesting. Some of the some
Speaker 1: of this to me is counterintuitive. I'm sure to some
Speaker 1: people are like, this all makes perfect sense. I don't
Speaker 1: know what you're talking about with counterintuitive. But I remember
Speaker 1: the first time I read about they were using a
Speaker 1: hockey stick as a an example of a third class
Speaker 1: leaver from one of the sources. I was looking over
Speaker 1: and I thought, I'm from Georgia. That example means nothing
Speaker 1: to me. And then they said baseball band, Like okay,
Speaker 1: now I understand what you're saying. Next, we have another
Speaker 1: simple machine, the inclined plane. It is so inclined it's
Speaker 1: the simplest of all simple machines. Perhaps it's it's definitely,
Speaker 1: I mean it's it's essentially a ramp, you know, that's
Speaker 1: really what is So when you want to move, when
Speaker 1: you want to move a load from one elevation to
Speaker 1: a different elevation and it's too heavy to just lift,
Speaker 1: a ramp can often help out. It decreases the amount
Speaker 1: of force you need to get the load to that height,
Speaker 1: but it increases the distance you must travel in order
Speaker 1: to do so. So when we were talking earlier about
Speaker 1: the wheels and the logs, and you know this this
Speaker 1: concept of how much time is it going to take
Speaker 1: to do this? Uh, the pyramids were built by moving
Speaker 1: these enormous blocks of stone up very long ramps to
Speaker 1: get to their their various elevations, because the blocks of
Speaker 1: stone are far too heavy to just lift and put
Speaker 1: them in place. Wow. I think for a long time
Speaker 1: we didn't know how they were built, right, Yeah, No,
Speaker 1: there was a lot of speculation about how it actually happened.
Speaker 1: But as it turns out, the ramp method is the
Speaker 1: one that was used to. You know, if you build
Speaker 1: the ramp out long enough, then you decrease that force
Speaker 1: to make it more manageable. But you do have to
Speaker 1: make the ramp longer and longer to increase that mechanical advantage. Right,
Speaker 1: That does mean you have to travel further and further.
Speaker 1: It makes sense because you know, you just intuitively understand
Speaker 1: that a short ramp is going to be much more steep,
Speaker 1: and that steepness is going to make make it so
Speaker 1: that you have to apply more force to get whatever
Speaker 1: the load is up that ramp that you're familiar with.
Speaker 1: This in simple walking terms, I mean you take fewer
Speaker 1: steps going up a short steep incline to the same
Speaker 1: altitude versus a very long, slow, gradual slope to an
Speaker 1: equal altitude, but you but it's still you know, easier
Speaker 1: taking the long, slow way. You're still doing the same
Speaker 1: amount of work overall, because again it's force times distance,
Speaker 1: but you're doing less force per unit of walking, so
Speaker 1: it doesn't feel like it's as exhausting unless the ramp
Speaker 1: is so long as to make the journey intolerably long,
Speaker 1: which could be a possibility if you have enough space,
Speaker 1: but infinite ramp that's a good band name. Yeah, yeah,
Speaker 1: I have a feeling that just just be a jam band,
Speaker 1: play those like incredibly long jam sessions that don't ever
Speaker 1: go anywhere. But yeah, if you were to take that
Speaker 1: same weight we were talking about that fifty pound weight
Speaker 1: we were mentioning earlier, we have a ramp that's two
Speaker 1: ft tall and four ft long. It'll take half the
Speaker 1: amount of force needed to get it moving over twice
Speaker 1: the distance of just lifting it up those two feet,
Speaker 1: so again saves you the force needed to move this thing. Uh.
Speaker 1: Then making that ramp longer would decrease the steepness and
Speaker 1: the force needed to move the weight even further, but
Speaker 1: it would increase the distance at the same time. And
Speaker 1: now we start getting into some of the the advanced
Speaker 1: simple machines. The ones we've named so far are really
Speaker 1: you know, most people argue this is the the furthest
Speaker 1: you can break down a simple machine. The other ones
Speaker 1: have some elements to them that are similar to the
Speaker 1: previous ones, like the pulley, which is kind of similar
Speaker 1: to levers and also to wheel and axle. I feel like, maybe,
Speaker 1: of all the simple machines, I encounter a pulley, the
Speaker 1: least often in my life, at least at least visibly. Yeah, right,
Speaker 1: so pully, maybe if I were a sailor, yeah we
Speaker 1: we You probably know what a pulley looks like. Um,
Speaker 1: generally speaking, you've got like a grooved wheel that's suspended
Speaker 1: within a frame, can spin freely within that frame. You
Speaker 1: feed a rope through it, or line through it if
Speaker 1: you're a sailor. Uh. And this allows you to change
Speaker 1: the direction of force, but it doesn't change the amount
Speaker 1: of force you need to move awight all by itself.
Speaker 1: So so changing the direction of force, even if you're
Speaker 1: not adding force can be very useful because, as everyone knows,
Speaker 1: it's much easier to pull down on something using your
Speaker 1: body weight and gravity to advantage than it is to
Speaker 1: push up with the same force. Right. So, and I
Speaker 1: should clarify when I say this, I'm really talking about
Speaker 1: a suspen ended pulley from like a beam or some
Speaker 1: other stationary object. And the weight you want doesn't have
Speaker 1: a pulley attached to it, because you could attach a
Speaker 1: pulley to the weight and then tie one end off
Speaker 1: to something like a beam and you could hold the
Speaker 1: other end, in which case it doesn't reverse the direction
Speaker 1: of the force. Right, you are pulling up, but it
Speaker 1: reduces the amount of force you need to lift the weight.
Speaker 1: So if you if you do it that way, where
Speaker 1: the beam is holding one end of the rope and
Speaker 1: you're holding the other end of the rope, you're reducing
Speaker 1: the amount of force, but you're not changing the direction. If,
Speaker 1: on the other hand, the beam is holding the pulley
Speaker 1: and the rope is just attached to a weight, you're
Speaker 1: reversing the direction, but you're not reducing the amount of force. Um.
Speaker 1: But I bet there is a way to reduce the
Speaker 1: amount of force. Yeah, you just gotta add more police.
Speaker 1: So let's say we put how how many you got, Joe?
Speaker 1: Have you heard of block and tackle? All right? First,
Speaker 1: let's let's go with the simplest approach, where we have
Speaker 1: two pullice. Let's say you have one pulley attack matched
Speaker 1: to a stationary thing like a beam hanging from the roof, right,
Speaker 1: and then you have a second pulley that's attached to
Speaker 1: the weight that you plan on moving. You tie one
Speaker 1: end of your line off onto the beam or even
Speaker 1: onto that that first pulley that we're talking about, feed
Speaker 1: the line down through the pulley that's attached to the weight,
Speaker 1: feed that line up through the pulley that's attached to
Speaker 1: the beam, and then you finally hold the other end.
Speaker 1: You pull down, and now the weight has been reduced
Speaker 1: the amount of force you need, or at least the
Speaker 1: perceivable weight you feel. The amount of force you need
Speaker 1: to move that weight has been reduced a half. But
Speaker 1: you have to move twice as you have to pull
Speaker 1: twice as far, twice as much rope to move it
Speaker 1: the distance that you want to go. So, in other words,
Speaker 1: if you want the symmetry of physics is beautiful, So
Speaker 1: if you want to have lifted that two feet, you
Speaker 1: have to pull four ft of rope, all right, But
Speaker 1: you could add more pulleys and this would decrease the
Speaker 1: amount of force further while increasing the amount of instance more.
Speaker 1: You would actually have to have longer rope obviously, if
Speaker 1: you started to add lots and lots of of pulleys
Speaker 1: and you had a full block and tackle system. But
Speaker 1: this would allow you to move incredible weights using a
Speaker 1: relatively small amount of force. You would just have to
Speaker 1: be willing to pull lots of rope in order to
Speaker 1: do it, or line all all of the sailors who
Speaker 1: listen are just singing. There's such a rube saying rope.
Speaker 1: I guess maybe they don't like the word rope. It's
Speaker 1: it's line. It's not rope, it's line on a ship. Yeah,
Speaker 1: I spent a little, tiny, tiny amount of time on
Speaker 1: a ship and I got I got corrected so many times. Well,
Speaker 1: we should have a face off between geometris, geometrs, geometricians,
Speaker 1: geo geometris, geometry, geometry stars. I think, yeah, I think
Speaker 1: of geometry as trickery, so I I my vote goes
Speaker 1: to the geometric stars, geometry teachers, and sailors, and they
Speaker 1: can argue about lines. I knew some geometry teachers who
Speaker 1: could definitely take on some sailors in their time. Okay,
Speaker 1: let's let's do another one. All right, sure, what what
Speaker 1: do you want to do? The screw? The simple machine? Right? Yes,
Speaker 1: I am so, if I'm not mistaken. The screw is
Speaker 1: basically just an inclined plane in a particular configuration. Yeah,
Speaker 1: it's an inclined plane that is wrapped around the core
Speaker 1: of something like a like a shaft. Do you take
Speaker 1: a shaft, you put an inclined plane and you spiral
Speaker 1: it around the shaft and you get a screw and uh,
Speaker 1: screws can it's a tiny circular ramp. Yeah, And that
Speaker 1: circular part is what's really important, because it means that
Speaker 1: if you apply a rotational force to the screw, it
Speaker 1: provides a linear force along the length of the shaft
Speaker 1: that is greater than the force you use to turn
Speaker 1: the screw in the first place. Uh. This of course
Speaker 1: is dependent upon the pitch. The pitch the pitch and
Speaker 1: screws is. The description is that it's the distance between
Speaker 1: the treads. So the the sections of the ramp, the
Speaker 1: closer together they are, the greater the ideal mechanical advantage.
Speaker 1: And the reason is the mechanical advantages dependent upon the
Speaker 1: length of the inclined plane the ramp to the length
Speaker 1: of the shaft. So if the treads are closer together,
Speaker 1: that means if you were to untwirl this, the ramp
Speaker 1: would be much much much longer because the cram more
Speaker 1: of it along the length of the screw. Yeah, that
Speaker 1: makes sense. So yeah, that's like having that longer, slower
Speaker 1: gradient of ramp up to the summit, right exactly. Yeah,
Speaker 1: So it's interesting to think of it that way, but yeah,
Speaker 1: the treads are closer together, it's going to exert a
Speaker 1: greater force when you turn this this. These of course,
Speaker 1: have been really useful in lots of different uh applications,
Speaker 1: everything from you know, just securing something to the wall,
Speaker 1: for example, because it has a great holding force that
Speaker 1: way to lifting things our comedies, screw was a way
Speaker 1: of drawing water out, which was kind of cool. Um.
Speaker 1: You know, it's it's an interesting simple machine, and it's
Speaker 1: something that if you were to look at, like you
Speaker 1: go to a hardware store and you look at a
Speaker 1: bunch of screws, you wouldn't necessarily think this is a machine, right.
Speaker 1: You think of it as a tool or or you know,
Speaker 1: just something that you need. But it actually is one
Speaker 1: of the simple machines. And only is it one of
Speaker 1: the simple machines, but like we're pointing out, it's a
Speaker 1: simple machine that's made up of an even simpler machine,
Speaker 1: which is kind of cool. Um. Yeah, it's an interesting,
Speaker 1: uh piece of machinery, if you if you will. And
Speaker 1: the earliest evidence of screws come from Greece. Uh so
Speaker 1: they were actually one of the later simple machines to
Speaker 1: arrive on the scene and the grand scheme of things
Speaker 1: comedies had had a screwed. Yeah, yeah, that was the
Speaker 1: one that drew water up. Yeah, the water the water
Speaker 1: screw Yep, it's really cool. If you've never seen any
Speaker 1: illustrations of that, you should look it up. Our comedies
Speaker 1: screw is pretty cool. I think we talked out it,
Speaker 1: and we did a tech stuff podcast ages ago about
Speaker 1: our comedes, and I'm pretty sure we talked about our
Speaker 1: community screw. We we spent a lot of that time.
Speaker 1: That was a Crisp Palette episode, and we've been a
Speaker 1: lot of that time talking about some of the crazy
Speaker 1: inventions attributed to our commedes, perhaps apocryphal e Like the
Speaker 1: claw that reaches out of the city walls and grab ships.
Speaker 1: That was one of them. Yeah. Alright, so let's talk
Speaker 1: about the last of the simple machines. Yet another application
Speaker 1: of the ramp, right, Yeah, this is the wedge. So
Speaker 1: a wedge is essentially two inclined ramps that are against
Speaker 1: each other to create this wedge shape. And uh, they
Speaker 1: can be used to do a couple of different things.
Speaker 1: They can be driven beneath a weight to lift it up.
Speaker 1: So this would be you know, a wedge that you
Speaker 1: would you would put the end of it under the weight,
Speaker 1: and you would apply force to the the flat end
Speaker 1: of the wedge, the back end, the butt end of it,
Speaker 1: and that would end up pushing the weight upward because
Speaker 1: of the the design of the wedge, or you could
Speaker 1: use it to be destructive. So, Jonathan, I have a
Speaker 1: question for you as away Joe. Have you ever split
Speaker 1: wood with a mall? I want split wood with Darth mall. No,
Speaker 1: I'm serious now, no lightsaber jokes. Have you ever split
Speaker 1: wood with a mall? I have not. I've only split
Speaker 1: wood with axes, which are not necessarily easy tools to
Speaker 1: use for that purpose. Well, a splitting mall is. It's
Speaker 1: hard work, but man, it is a really satisfying feeling.
Speaker 1: So imagine it's sort of like an ax. Uh. It
Speaker 1: is a sort of a combination of an ax and
Speaker 1: a sledge hammer. If you can imagine that it's a
Speaker 1: long handle and then at the end of the handle
Speaker 1: you have this bulky heavy head that is basically a
Speaker 1: wedge on one end and then a sledge hammer on
Speaker 1: the other. Just I think to increase the weight basically,
Speaker 1: and the wedge doesn't even necessarily have to be that sharp.
Speaker 1: I think it usually isn't. The one I used wasn't
Speaker 1: very sharp, but because of the weight, it was a
Speaker 1: one hit splitter. So you'd put a log segment out
Speaker 1: and you'd hit it once and it would just cleave apart,
Speaker 1: which is pretty impressive. Yeah. Oh man, it it felt
Speaker 1: good to do, but it got tiring after a while. Yeah,
Speaker 1: And see you can see that there's some like within
Speaker 1: the mall. There are two machines here at work. Right,
Speaker 1: You've got the lever as far as the handle, that's
Speaker 1: what's allowing you to apply leverage when you're doing your swing,
Speaker 1: and then you have the wedge, which is doing the
Speaker 1: actual splitting. So the wedge, what it's doing is it's
Speaker 1: applying that downward force and changing the direction of that
Speaker 1: forced to outward. Yeah, so that's why you when you
Speaker 1: hit the log, that outward force splits the log apart,
Speaker 1: and it's really cool. I try doing the same thing
Speaker 1: with acess, which you can do, but it takes more effort, yeah,
Speaker 1: because the axe head probably just doesn't heavy enough that. Yeah,
Speaker 1: it's you know, you're using so you have to take
Speaker 1: up some of the four that normally would have been
Speaker 1: taken care of by the the tool itself. It's pretty cool.
Speaker 1: I've never done that now. Uh it's yeah, give it
Speaker 1: a shot sometimes. All right, next time I'm out in
Speaker 1: the woods and I'm just thinking, you know what I
Speaker 1: need to do, it's just split get your hands on
Speaker 1: the mall. You know, my family actually called it a maddic.
Speaker 1: I had to look it up and figure out that
Speaker 1: I was wrong about what a mattock was. A matic
Speaker 1: is a thing with a differently oriented head. It's kind
Speaker 1: of like a pick axe got you. But that was
Speaker 1: just how your family referred to it. It was a mall.
Speaker 1: I have determined now, So yeah, these are that's the
Speaker 1: that's the last of the six simple ones. But then
Speaker 1: there are also other machines that we can talk about,
Speaker 1: compound machines. I mentioned those earlier. These are the machines
Speaker 1: that combined two or more simple ones. Ship's home is
Speaker 1: one of the examples. We've already talked about. Wheelbarrow was
Speaker 1: another one we talked about. Scissors would be a great
Speaker 1: example because with scissors, you've got a pair of wedges.
Speaker 1: Those would be the blades of the scissors, and you
Speaker 1: have a lever. The handle that you hold would be
Speaker 1: a lever the fulcrum would be the center that that
Speaker 1: binds them together. Uh, and so that's what allows you
Speaker 1: to use scissors. Compound machines have more moving parts than
Speaker 1: simple machines, but that's not necessarily a good thing overall,
Speaker 1: because the more parts you have, the more you have
Speaker 1: to overcome friction. If you add lots and lots of
Speaker 1: different parts, that friction could be very difficult to overcome
Speaker 1: and it could end up generating a lot of heat,
Speaker 1: which is why very complex machines like a car engine
Speaker 1: require coolens and lubricants in order for them to continue
Speaker 1: to work properly. Um. That means there's also a loss
Speaker 1: and efficiency. However, the compound machines have greater mechanical advantage.
Speaker 1: You actually multiply the problem. You multiply the mechanical advantage
Speaker 1: of each of the individual um simple machines within the
Speaker 1: compound machine to determine what its mechanical advantages. So as
Speaker 1: long as every single simple machine in your compound machine
Speaker 1: has that ideal mechanical advantage of greater than one, the
Speaker 1: more you add, the greater mechanical advantage the compound machine has,
Speaker 1: and thus we get to the Roobe Goldberg device. Yeah,
Speaker 1: what what's it has? Like a goldfish that operates a
Speaker 1: magnifying glass that burns a rope and yeah, exactly, and
Speaker 1: then you get an okay go video out of it.
Speaker 1: Not all those would be simple machines, I don't think
Speaker 1: the magnifying glass, but even some of those would be
Speaker 1: compound machines. That would be a collection of simple machines.
Speaker 1: But there you go. That's the collection of simple machines
Speaker 1: and what they do and why they're important. Um, it's
Speaker 1: it was fun to look back at this, even though,
Speaker 1: like again, this is something that any of our listeners
Speaker 1: who are still in school, they may be rolling their
Speaker 1: eyes for the whole thing because they're thinking they've already
Speaker 1: learned all this stuff and that this is repetitive. But
Speaker 1: for those of us who graduated a long time ago
Speaker 1: and perhaps have not kept up with physics the way
Speaker 1: we might have wanted to. I loved physics when I
Speaker 1: was a kid. It was one of my favorite, m
Speaker 1: favorite subjects in school. I wish I had appreciated science
Speaker 1: more when I was in school. I didn't. I didn't
Speaker 1: really come to love science until after I was out
Speaker 1: of school, and then I wished I could go back
Speaker 1: and and treat it with the respect it deserves. Out
Speaker 1: of all the sciences, uh, classical physics was the one
Speaker 1: that appealed to me most because it was the one
Speaker 1: that made sense to me because it was it was
Speaker 1: the physics of the world that I could observe around me,
Speaker 1: and I loved it. I just I understood it and
Speaker 1: I took to it. Not so much with the biology
Speaker 1: and chemistry as it terms. I mean I I did well,
Speaker 1: but they were harder. They were harder to learn for me.
Speaker 1: Uh So, anyway, this was a lot of fun to
Speaker 1: go back and look at. If you guys have any
Speaker 1: questions comments things like that, then I recommend you right
Speaker 1: in my addresses tech stuff at how stuffworks dot com
Speaker 1: or dropped me a line on Twitter or Facebook or Tumblr.
Speaker 1: The handle of all three is tech stuff hsw Joe.
Speaker 1: Where can they find you orr work? Well, you can
Speaker 1: go to fw thinking dot com where I am one
Speaker 1: of the hosts along with Jonathan and Lauren Bogelbaum, of
Speaker 1: the Forward Thinking podcast. I also write for the videos
Speaker 1: that Jonathan does there with with great skill and success
Speaker 1: and charisma and charm. Oh I thought you were talking
Speaker 1: about your own writing abilities right, with great skill and
Speaker 1: success and and and shiny nous of head. There's incredible
Speaker 1: modesty going on as well. You can also check out
Speaker 1: the how Stuff Works YouTube page to see plenty of
Speaker 1: the videos I write I write per how Stuff Works
Speaker 1: video yep, and you also appear in them occasionally occasionally. Yeah,
Speaker 1: you know. The the Hot Sauce Guy is still my
Speaker 1: favorite appearance by Joe mcformance so far. Um, but there
Speaker 1: have been some really good ones, So go check that
Speaker 1: out and we will talk to you again. Really for
Speaker 1: more on this and bathands of other topics. Because it
Speaker 1: has to works, dot com is chas