Speaker 1: Welcome to tech Stuff, a production from I Heart Radio.
Speaker 1: Hey there, and welcome to tech Stuff. I'm your host,
Speaker 1: Jovian Strickland. I'm an executive producer with I Heart Radio
Speaker 1: and I love all things tech. It is time for
Speaker 1: a tech Stuff classic episode. This episode originally published February
Speaker 1: twenty three, two thousand and fifteen. It is titled The
Speaker 1: Six Simple Machines Enjoy. Have you all ever done a
Speaker 1: podcast on the six classical simple Machines? If not, that
Speaker 1: might make for an interesting topic. Oh I remember these
Speaker 1: from school? I do too, is except I don't remember them.
Speaker 1: What were they? There was the toaster, There was the
Speaker 1: what the electric camera? Yeah? I think I'm pretty sure
Speaker 1: the A T M was on their nail gun, right,
Speaker 1: that's way up there? Yeah, and uh I think, uh,
Speaker 1: I think perpetual motion. That was one was really simple.
Speaker 1: It just kept going. The machine simple and it also
Speaker 1: know as the clock. Yes, yeah, yeah, no, of course
Speaker 1: the six Simple Machines are far simpler than that, but
Speaker 1: they are really important. They form the basis of a
Speaker 1: lot of the machines that we use today, and ultimately,
Speaker 1: most importantly, they make work easier. Work is hard work
Speaker 1: is hard, work is hard to explain unless you're a
Speaker 1: physics teacher and you do it all the time. But
Speaker 1: it has been many, many years since I took a
Speaker 1: course in physics, and while I still understand and appreciate
Speaker 1: simple machines and the concepts of work and force and
Speaker 1: this sort of thing, it behooved me to do a
Speaker 1: quick refresher course before doing this podcast. We'll share your
Speaker 1: knowledge with this, Jonathan. All right, So work is force
Speaker 1: acting on an object in the direction of motion. Uh.
Speaker 1: And so you could think of it in the equation
Speaker 1: of force times distance equals work. All right. Uh. So
Speaker 1: this is why we we express work in units of
Speaker 1: force and time, such as a Newton meter and a newton.
Speaker 1: Since this raises the next question, a newton is the
Speaker 1: amount of force required to accelerate one m of mass
Speaker 1: at one per second squared. So these are the basic
Speaker 1: units we're talking about, although we'll also be talking about
Speaker 1: uh pound foot as a means of a unit of measurement.
Speaker 1: Because we're in America and we use antiquated systems of
Speaker 1: units in our measurements. Then we can't understand how to
Speaker 1: use this funky you know, metric system approach or or
Speaker 1: the standard unit approach. Okay, but wait a second, how
Speaker 1: is work different from force? So force is an agent
Speaker 1: that results in accelerating or deforming an object. So if
Speaker 1: you want to get an object to start moving, you
Speaker 1: have to apply force to it. If you want to
Speaker 1: punch a hole in a wall, you have to apply
Speaker 1: force to it. But work is the force acting on
Speaker 1: that object in the direction of motion. So it's it's
Speaker 1: it's a it's it encompasses more than just the force. Okay.
Speaker 1: So if I pushed a wheelbarrow twenty feet over a
Speaker 1: certain period of time, that would be work, right, But
Speaker 1: your actual pushing against the wheelbarrow itself is force, So
Speaker 1: you know, it's it's kind of a perspective thing in
Speaker 1: a way. But it's very important when you start talking
Speaker 1: about how much how much work and actual task is
Speaker 1: versus the amount of force that you have to do
Speaker 1: to accomplish that task. Okay, And so machines in the
Speaker 1: simplest way, are something that helps us do work easier, right, Yeah,
Speaker 1: so that we either have to do the work with
Speaker 1: less force or uh. Really, machines can change the dynamics
Speaker 1: of force and distance an interesting way, and sometimes it's
Speaker 1: ways that might seem counterintuitive to you will definitely talk
Speaker 1: about something that seems counterintuitive, at least the fort when
Speaker 1: I first thought of it, it was counterintuitive when we
Speaker 1: get to h levers, which spoiler alert are actually one
Speaker 1: of the six. But at any rate, yeah, it means
Speaker 1: that we don't have to exert as much energy when
Speaker 1: we are trying to accomplish this task, the specific type
Speaker 1: of work, whatever that might be. And that was really important.
Speaker 1: I mean, obviously in early the early days of humanity,
Speaker 1: you know, we spent most of our effort just trying
Speaker 1: to make sure we weren't dying, and anything that would
Speaker 1: save us that kind of effort meant that we could
Speaker 1: we could reserve more energy for very important things like
Speaker 1: running away. It's a big one, yeah, But at any rate,
Speaker 1: so there are four main ways that machines make work easier,
Speaker 1: and the first is that he can increase the magnitude
Speaker 1: of a force. So they essentially amplify the amount of
Speaker 1: force being applied to an object or system. So you
Speaker 1: are are exerting a certain force upon a machine, the
Speaker 1: machine amplifies that force applied to whatever the load is.
Speaker 1: That's usually what we call the the thing that you're
Speaker 1: having the machine act upon and it amplifies that force
Speaker 1: so that the load is is experiencing more force being
Speaker 1: exerted upon it than you are putting into the machine. Okay,
Speaker 1: so in early humanity terms, you might think of this
Speaker 1: as something like an AX, right, yeah, that would be one,
Speaker 1: uh you know, any or a ramp, just a simple ramp,
Speaker 1: because you would you would be exerting less force to
Speaker 1: move the object as if you wanted. Let's say you
Speaker 1: wanted to move an object, huh to a allege that's
Speaker 1: ten ft above ground level, and if you were to
Speaker 1: actually just lift that object physically, it would require a
Speaker 1: certain amount of force on your side. But if you
Speaker 1: used a ramp, it would decrease, especially a very long,
Speaker 1: gradually sloped ramp, It would decrease the amount of force
Speaker 1: you needed to get the thing moving. It would just
Speaker 1: increase the amount of distance you would have to travel
Speaker 1: to get it to where it needs to go. We'll
Speaker 1: talk more about that in a bit. Oh yeah, well,
Speaker 1: I guess an AX would actually involve more than one
Speaker 1: kind of simple machine because it has an inclined plane
Speaker 1: or a wedge on it. Yeah, I thought so, maybe
Speaker 1: what I should have said would be a club, Yeah,
Speaker 1: a club that would magnify force, right, yeah. Yeah. There's
Speaker 1: also the the idea of transferring a force from one
Speaker 1: place to another, which 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 of this would be a lever or a
Speaker 1: pulley where you know the classic lever where I might
Speaker 1: like it. With a classic leaver, I pushed down on
Speaker 1: one side, the other side goes up, so I'm actually
Speaker 1: pushing the opposite direction of where the force is being applied. Okay,
Speaker 1: so like a seesaw. Yeah. Then there's also the increasing
Speaker 1: the distance or speed of a force, which is a
Speaker 1: pretty simple concept. Uh. And this is the one that
Speaker 1: to me was the most counterintuitive when we get to levers,
Speaker 1: but I want to save that for when we get there.
Speaker 1: And of course, a combination of machines can create a
Speaker 1: wide array of effects, and we'll talk about some compound
Speaker 1: machines which are uh, you know it's obviously two or
Speaker 1: more simple machines put together to make something more complex. Okay,
Speaker 1: well one of these simple machines has got to be
Speaker 1: the wheel, right, well, wheel and axle to be to
Speaker 1: be specific. But yes, yeah, I guess without an axle,
Speaker 1: wheel isn't not as useful, no it you know, they're
Speaker 1: essentially POGs. Yeah, you could push it a little bit
Speaker 1: and then you'd have to keep putting it back under
Speaker 1: the thing. Yeah. In fact, that's exactly how early humans
Speaker 1: were moving large weights. They would have a collection of
Speaker 1: logs and they would lay those out on the ground,
Speaker 1: place a heavy weight on top of the logs. They
Speaker 1: pushed the heavy weight. The heavy weight would roll across
Speaker 1: the tops of those logs. But that would mean that
Speaker 1: you get closer to the edge, right, you're the the
Speaker 1: end of the object. We get closer to the last
Speaker 1: remaining log in the front. You would have to pick
Speaker 1: up the logs in the back, run around, put them
Speaker 1: down in front of everything. Was not the most efficient
Speaker 1: means of getting a heavy weight from point A to
Speaker 1: point B. I bet that was a fun job. Yeah,
Speaker 1: I mean, now, granted, when all you're trying to do
Speaker 1: is build a megalithic structure to sacrifice humans on. Well,
Speaker 1: and here's the thing, the people who were building said
Speaker 1: megalithic structures often time was not something they were really
Speaker 1: that concerned about. Yeah, but at any rate, Um, if
Speaker 1: you're looking at the wheel and axel, we believe that
Speaker 1: was invented sometime around thirty five hundred b c E. Yeah,
Speaker 1: the earliest evidence actually comes from thirty two hundred from
Speaker 1: Sumerian artifacts. And also it appears to have been independently
Speaker 1: invented in China around Okay, so not shared from the Sumerians,
Speaker 1: but different people came up with the same idea. Yes,
Speaker 1: that 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 the research I
Speaker 1: read suggested that in fact it did appear independently, which
Speaker 1: is kind of cool. Yeah, 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 always 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 you know, vehicles, then you're really stuck
Speaker 1: literally in some cases. So yeah, the wheel reduces friction, right,
Speaker 1: that's 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 act
Speaker 1: to the wheel. The wheel just rotates around the axle.
Speaker 1: And then there's the fixed that that one would be
Speaker 1: fixed to the frame of the cart, so the axle
Speaker 1: is fixed and the wheel moved right. 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 axle will have to move together,
Speaker 1: which you know, you look at cars, Yeah, you know,
Speaker 1: if if all of our cars had each wheel moving independently,
Speaker 1: and 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 went and get our stuff to where
Speaker 1: it needs to be. It would be tough. Uh. So
Speaker 1: another 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. It's 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. Yeah. Okay, Now what that
Speaker 1: means for us is that you can use a wheel
Speaker 1: as 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, and I'm sure it took
Speaker 1: a 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
Speaker 1: or sorry, it would be a nut. I guess a nut.
Speaker 1: And it is really hard to loosen. It takes a
Speaker 1: lot of force to do it. You can do it
Speaker 1: by having a longer handle on your wrench. The longer
Speaker 1: the handle, 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 a circle right for you to get that
Speaker 1: that nut to go one complete rotation. But it's far
Speaker 1: easier as far as the amount of force applied. I
Speaker 1: like that you pronounce it lever and I pronounce it lever.
Speaker 1: It's gonna get really interesting when we're talking about leverage.
Speaker 1: So the data data, Yeah, this is the device that
Speaker 1: gives us a leverage, and which is really how I
Speaker 1: would say it. I don't know why I say lever
Speaker 1: but then I say leverage. I just don't. I guess
Speaker 1: it's you know, it's just because that song you know,
Speaker 1: fifty ways to love your lever. Okay, never mind, you
Speaker 1: 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: liver 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 uh,
Speaker 1: the way this works is depending on what side is longer,
Speaker 1: that's going to travel more distance and and apply less force.
Speaker 1: So if you have a weight, and you put the
Speaker 1: short side of a beam under that weight, and then
Speaker 1: you got a fulcrum there, and then the long side
Speaker 1: of the beam is the one that you pushed down on.
Speaker 1: You have to push further to make the weight go
Speaker 1: up the distance you wanted to go, but you're using
Speaker 1: less force than you would if you were to just
Speaker 1: lift the weight up bodily, straight up. So we thought
Speaker 1: this would be easier to understand with an example. So
Speaker 1: imagine that you've got a fifty pound weight. I'm just
Speaker 1: gonna do a little bit of metrics here just at
Speaker 1: the beginning, and then I apologize. You're just gonna have
Speaker 1: to use conversions to convert everything over because I didn't
Speaker 1: do it for everything. But if you're talking about fifty pounds,
Speaker 1: that's about twenty two point seven trams and you want
Speaker 1: to lift it up two feet, which is about point
Speaker 1: six meters. To do this, you have to do a
Speaker 1: hundred pound feet of work or one thirty five point
Speaker 1: six newt meters of work, because again it's force times distance.
Speaker 1: So you'd have the uh fifty pounds of weight times
Speaker 1: the two feet, and that gets the hundred pound foot work. Now,
Speaker 1: if you used a lever that was twenty ft long
Speaker 1: on one side and then ten feet on the other side.
Speaker 1: So so the side that you're going to apply force too,
Speaker 1: it's twice as long. And you've got a fulcrum that's
Speaker 1: just uh that's one ft tall. It would be half
Speaker 1: the amount of force you would need to lift that
Speaker 1: load than before um, so it you know, it's it's
Speaker 1: much easier. And of course if you were to extend
Speaker 1: the lever longer, it would be less and less force,
Speaker 1: but you have to travel greater distances to get it
Speaker 1: up the two feet that you want. This is why
Speaker 1: you have the famous possibly apocryphal quote, uh that our
Speaker 1: committees said that he said if he had a lever
Speaker 1: long enough, he could move the world. I guess that's
Speaker 1: probably true. Yeah, I guess, well, no, I don't probably
Speaker 1: using it would depend It would depend on what the
Speaker 1: the lever or lever was made of, wouldn't it. Because
Speaker 1: at a certain point, when you're trying to move things
Speaker 1: of great enough mass are taking enough force to move,
Speaker 1: you'd reach the breaking point of your lever, wouldn't you. Well, yeah,
Speaker 1: I mean, if you had something that was that long,
Speaker 1: unless it had incredible strength, it would uh, it would
Speaker 1: break under its own weight. We'll be back with more
Speaker 1: of the six simple machines after these brief messages. So
Speaker 1: leavers change the direction or they can change the direction
Speaker 1: of an applied force, but depends upon the input and
Speaker 1: output output forces relative to the fulcrum. And there are
Speaker 1: three classes of levers. So the one we just talked
Speaker 1: about that example, the you got the it's it's like
Speaker 1: the seesaw looking type of lever. That's a the first
Speaker 1: class style of lever. Okay, So one side of the
Speaker 1: seesaw is longer than the other side. You can use
Speaker 1: the longer side to lift heavier loads. And it also
Speaker 1: changes the direction of the applied force. That's one of
Speaker 1: the one of the elements of it. The second class
Speaker 1: is more like a wheelbarrow, which involves too simple machines.
Speaker 1: You have the wheel and axle, but you also have levers.
Speaker 1: The handles act as levers. Now in that case, the
Speaker 1: fulcrumb is on one end of the entire beam. Think
Speaker 1: of the handles as a beam. So the fulcrumb in
Speaker 1: this case the wheel is weigh on one end. Then
Speaker 1: you have the load, which is the actually little load
Speaker 1: that's inside the wheelbarrow. Then you have the handles the
Speaker 1: input that you create. So it's different from the seesaw right,
Speaker 1: where you would have the fulcrum in the center. Now
Speaker 1: you have the fulcrum on the end, then the load
Speaker 1: and then you lifting it this one. Instead of reversing
Speaker 1: the direction of the force, it's the same direction right
Speaker 1: because you're lifting up on a wheelbarrow, handles and it
Speaker 1: and it lifts the load up as well. So it's
Speaker 1: different from uh, the first class of leavers. The third
Speaker 1: class is the one that seems the most counterintuitive if
Speaker 1: you first think about it. So would the flat end
Speaker 1: of a crowbar be a second class lever because they're
Speaker 1: what you're doing is you don't have the full crumb
Speaker 1: in the middle. You're you're pressing the end against the
Speaker 1: inside of the door frame, say, and then a little
Speaker 1: bit further towards the end you're holding is what's mashing
Speaker 1: against the door and you're using it to pry like
Speaker 1: a prying action. Seems like second class levers. It is,
Speaker 1: And of course, if you were to turn the crowbar
Speaker 1: around to use the curved end be a first class
Speaker 1: just like a Claude hammer would be as well. Here's
Speaker 1: a Claude hammer to remove nails. Uh, so that's a
Speaker 1: great example. Third class levers are the ones to me
Speaker 1: that are the most counterintuitive. Um they have the fulcrum
Speaker 1: at one end, then you have the input force, then
Speaker 1: you have the output force. So you know when the
Speaker 1: wheelbarrow example, we've got input force on one end, then
Speaker 1: output in the middle, then the fulcrum in this case
Speaker 1: fulcrum input output. And you might think, wait a minute,
Speaker 1: what the how does that even work? It doesn't sound
Speaker 1: like and why would you want to use that? Because
Speaker 1: if you use if you use the sort of lever,
Speaker 1: it has what we call an ideal mechanical advantage of
Speaker 1: less than one ideal mechanical advantage. This is what's telling
Speaker 1: you how how how much it's helping you in the
Speaker 1: sense of how much force you have to apply versus
Speaker 1: the force that you're getting out of this too for
Speaker 1: the issue of making work right, So here you're you're
Speaker 1: actually at a loss. Yeah, and you might wonder, well,
Speaker 1: why would you want to do that? And the reason
Speaker 1: is that you are that output force has actually applied
Speaker 1: over a greater distance. So it's kind of the reverse
Speaker 1: of what we were talking about. Earlier about how with
Speaker 1: the wheel, when you have the greater distance, you have
Speaker 1: to apply less force, but you get more distance. In
Speaker 1: this case, you have to apply more forced down at
Speaker 1: 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 leaver. So this would
Speaker 1: be like my club example earlier exactly, that's essentially a
Speaker 1: third class lever or a first class bunk in 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 that are like, this all makes perfect sense. I
Speaker 1: don't know what you're talking about with counterintuitive, but I
Speaker 1: remember the first time I read about they were using
Speaker 1: a hockey stick as a an example of a third
Speaker 1: class lever from one of the sources. I was looking
Speaker 1: over and I thought, I'm from Georgia. That example means
Speaker 1: nothing to me. And then they said baseball band, Like, Okay,
Speaker 1: now I understand what you're saying. We're gonna wrap up
Speaker 1: the six simple machines in just a moment, but before
Speaker 1: we do that, let's take another quick break. Next, we
Speaker 1: have another simple machine, the inclined plane, and it is
Speaker 1: so inclined. It's the simplest of all simple machines. Perhaps
Speaker 1: it's it's definitely, I mean it's it's essentially a ramp,
Speaker 1: you know, that's really what is So when you want
Speaker 1: to move, when you want to move a load from
Speaker 1: one elevation to a different elevation and it's too heavy
Speaker 1: to just lift, a ramp can often help out. It
Speaker 1: decreases the amount of force you need to get the
Speaker 1: load to that height, but it increases the distance you
Speaker 1: must travel in order to do so. So when we
Speaker 1: were talking earlier about the wheels and the logs and
Speaker 1: you know, this this concept of how much time is
Speaker 1: it going to take to do this? Uh, the pyramids
Speaker 1: were built by moving these enormous blocks of stone up
Speaker 1: very long ramps to get to their their various elevations
Speaker 1: because the blocks of stone are far too heavy to
Speaker 1: just lift and put them in place. Wow. I think
Speaker 1: for a long time 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: and 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 four 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: can break down a simple machine. The other ones have
Speaker 1: some elements to them that are similar to the previous ones,
Speaker 1: like the pulley, which is kind of similar to levers
Speaker 1: 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, 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 a weight 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 tare 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 suspended pulley from like a beam or some other
Speaker 1: stationary object. And the weight you want doesn't have a
Speaker 1: pulley attached to it, because you could attach a pully
Speaker 1: to the weight and then tie one end off to
Speaker 1: something like a beam and you could hold the other end,
Speaker 1: in which case it doesn't reverse the direction of the force.
Speaker 1: Right you are pulling up, but it reduces the amount
Speaker 1: of force you need to lift the weight. So if
Speaker 1: you if you do it that way, where the beam
Speaker 1: is holding one end of the rope and you're holding
Speaker 1: the other end of the rope, you're reducing the amount
Speaker 1: of force, but you're not changing the direction. If, on
Speaker 1: the other hand, the beam is holding the pulley and
Speaker 1: the rope is just attached to a weight, you're reversing
Speaker 1: 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 many how many you got?
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 pulleys. Let's say you have one pulley attached to
Speaker 1: 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 wanted to go. So, in other words,
Speaker 1: if you want the symmetry of physics is beautiful. Yeah,
Speaker 1: so if you want to have lifted that two feet,
Speaker 1: you have to pull four feet of rope, all right,
Speaker 1: But you could add more pulleys and this would decrease
Speaker 1: the amount of force further while increasing the amount of
Speaker 1: distance more. You would actually have to have longer rope obviously,
Speaker 1: if you started to add lots and lots of of
Speaker 1: pulleys and you had a full block and tackle system.
Speaker 1: But this would allow you to move incredible weights using
Speaker 1: a relatively small amount of force. You would just have
Speaker 1: to be willing to pull lots of rope in order
Speaker 1: to do it. Or line all, all of the sailors
Speaker 1: who 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 and geometrs,
Speaker 1: geometricians and geometris, geomet geometrists or I think, Yeah, I
Speaker 1: think of geometry as trickery, so I I my vote
Speaker 1: goes to the geometric stars, geometry teachers, and sailors, and
Speaker 1: they can argue about lines. I knew some geometry teachers
Speaker 1: who 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. So 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, screws.
Speaker 1: Can it's a tiny circular ramp. Yeah, And that circular
Speaker 1: part is what's really important, because it means that if
Speaker 1: you apply a rotational force to the screw, it provides
Speaker 1: a linear force along the length of the shaft that
Speaker 1: is greater than the force you used to turn the
Speaker 1: screw in the first place. Uh. This, of course is
Speaker 1: dependent upon the pitch. The pitch. The pitch the pitch
Speaker 1: and screws is The description is that it's the distance
Speaker 1: between the treads. So the the sections of the ramp,
Speaker 1: the 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: every thing 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: had had a screwed. Yeah. Yeah, that was the one
Speaker 1: that drew water up. Yeah, the water the water screwe. Yep,
Speaker 1: it's really cool. If you've never seen any illustrations of that,
Speaker 1: you should look it up. Our commedie screw is pretty cool.
Speaker 1: I think we talked about it, and we did a
Speaker 1: tech Stuff podcast ages ago about our comedes, and I'm
Speaker 1: pretty sure we talked about our commedity screw. We we
Speaker 1: spent a lot of that time. That was a Cris
Speaker 1: Pallette episode, and we've been a lot of that time
Speaker 1: talking about some of the crazy inventions attributed to our commedes,
Speaker 1: perhaps apocryphal e Like the claw that reaches out of
Speaker 1: the city walls and grab ships. That was one of them. Yeah. Alright,
Speaker 1: so let's talk about the last of the simple machines.
Speaker 1: Yet another application of the ramp, right, Yeah, this is
Speaker 1: the wedge. So a wedge is essentially two inclined ramps
Speaker 1: that are against each other to create this wedge shape.
Speaker 1: And uh, they can be used to do a couple
Speaker 1: of different things. They can be driven beneath a weight
Speaker 1: to lift it up. So this would be you know
Speaker 1: a wedge that you would you would put the end
Speaker 1: of it under the weight, and you would apply force
Speaker 1: to the the flat end of the wedge, the back end,
Speaker 1: the butt end of it, and that would end up
Speaker 1: pushing the weight upward because of the the design of
Speaker 1: the wedge, or you could use it to be destructive.
Speaker 1: So Jonathan, I have a question for you. Ask away, Joe,
Speaker 1: have you ever split wood with a mall? I want
Speaker 1: split wood with Darth mall? No, I'm serious now, no
Speaker 1: lightsaber jokes. Have you ever split wood with a mall?
Speaker 1: I have not. I've only split wood with axes, which
Speaker 1: are not necessarily easy tools to use for that purpose. Well,
Speaker 1: a splitting mall is. It's hard work, but man, it
Speaker 1: is a really satisfying feeling. So imagine it's sort of
Speaker 1: like an ax. Uh. It is a sort of a
Speaker 1: combination of an ax and a sledge hammer. If you
Speaker 1: can imagine that it's a long handle and then at
Speaker 1: the end of the handle you have this bulky heavy
Speaker 1: head that is basically a wedge on one end and
Speaker 1: then a sledge hammer on the other. Just I think
Speaker 1: to increase the weight basically, and the wedge doesn't even
Speaker 1: necessarily have to be that sharp. I think it usually
Speaker 1: isn't the one I used wasn't very sharp, but because
Speaker 1: of the weight, it was a one hit splitter. So
Speaker 1: you'd put a log segment out and you'd hit it
Speaker 1: once and it would just cleave apart, which is pretty impressive. Yeah.
Speaker 1: Oh man, it it felt good to do, but it
Speaker 1: got tiring after a while. Yeah. And see you can
Speaker 1: see that there's some like within the mall. There are
Speaker 1: two machines here at work. Right, You've got the lever
Speaker 1: as far as the handle, that's what's allowing you to
Speaker 1: apply leverage when you're doing your swing, and then you
Speaker 1: have the wedge, which is doing the actual splitting. So
Speaker 1: the wedge, what it's doing is it's applying that downward
Speaker 1: force and changing the direction of that forced to outward. Yeah,
Speaker 1: so that's why you when you hit the log, that
Speaker 1: outward force splits the log apart. And it's really cool.
Speaker 1: I tried doing the same thing with access, which you
Speaker 1: can do, but it takes more effort, yeah, because the
Speaker 1: axe head probably just doesn't heavy enough that. Yeah, it's
Speaker 1: you know, you're using, so you have to take up
Speaker 1: some of the force that normally would have been taken
Speaker 1: 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 um, that's
Speaker 1: the that's the last of the six simple ones. But
Speaker 1: then 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 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. Uh,
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 individ dual um simple machines within
Speaker 1: the compound machine to determine what its mechanical advantages. So
Speaker 1: as long as every single simple machine in your compound
Speaker 1: machine has that ideal mechanical advantage of greater than one,
Speaker 1: the more you add, the greater mechanical advantage the compound
Speaker 1: machine has. And thus we get to the room 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 is repetitive. But for
Speaker 1: those of us who graduated a long time ago, and
Speaker 1: perhaps I have not kept up with physics the way
Speaker 1: we might have, you know, wanted to. I loved physics
Speaker 1: when I was a kid. It was one of my
Speaker 1: favorite favorite subjects in school. I wish I had appreciated
Speaker 1: science more when I was in school. I didn't. I
Speaker 1: didn't really come to love science until after I was
Speaker 1: out of school, and then I wished I could go
Speaker 1: back and and treat it with the respect it deserves.
Speaker 1: Out of all the sciences, uh, classical physics was the
Speaker 1: one that appealed to me most because it was the
Speaker 1: one that made sense to me, because it was it
Speaker 1: was the physics of the world that I could observe
Speaker 1: around me, and I loved it. I just I understood
Speaker 1: it and I took to it. Not so much with
Speaker 1: the biology and chemistry as it turns out. I mean,
Speaker 1: I did well, but they were harder. They were harder
Speaker 1: to learn for me. That wraps up the classic episode
Speaker 1: on the six Simple machines. I've seen so many cartoons
Speaker 1: that explained those and I love them so much. Uh,
Speaker 1: really fascinating stuff to me, like to think back on
Speaker 1: how these underlies so many machines today. I mean, at
Speaker 1: least the mechanical ones. Once you start getting into digital,
Speaker 1: it's a whole different ball game. But I hope you
Speaker 1: found that interesting. If you have suggestions for topics I
Speaker 1: should cover for future episodes of tech Stuff, please reach
Speaker 1: out to me. The best way to do that is
Speaker 1: on Twitter. To handle for the show is text stuff
Speaker 1: H s W and I'll talk to you again really soon.
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