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Speaker 1: Get in touch with technology with text stuff from dot com.

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Speaker 1: Hey there, and welcome to text stuff. I'm Jonathan Strickland,

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Speaker 1: and today I wanted to address some listener mail and

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Speaker 1: and do a full episode based upon a request. This

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Speaker 1: comes from Chris via email Now. Chris wrote an incredible email,

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Speaker 1: very long, lots of different stuff in it and lots

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Speaker 1: of different suggestions, one of which was about the topic

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Speaker 1: will be covering today. So here's that section of the email,

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Speaker 1: so don't don't be alarmed. I'm going in medias race.

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Speaker 1: This is the middle of the email here or really

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Speaker 1: the end. Lastly, I was hoping in the future to

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Speaker 1: see topics covered like how electronics work, transistors, capacitors, chips, etcetera.

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Speaker 1: I worked at radio Shack for five years and got

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Speaker 1: really interested in electronic components, but found them pretty confusing.

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Speaker 1: That is perfectly understandable. I still have to look up

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Speaker 1: the various components and remind myself what each one does

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Speaker 1: because I don't tend to work with electronic circuits that frequently,

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Speaker 1: and I know in general what needs to happen, but

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Speaker 1: sometimes I forget the specifics because there's a lot of

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Speaker 1: stuff there, and if you aren't familiar. If you're not

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Speaker 1: always working in that world, it can very easily slip

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Speaker 1: away from you. And we are talking about lots of

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Speaker 1: different components that you measure using different units, And after

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Speaker 1: a while you just start to you know, if you again,

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Speaker 1: if you're not just naturally inclined to this kind of stuff,

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Speaker 1: you start to pull your hair out. Except in my case,

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Speaker 1: that's already been done for me, so I just kind

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Speaker 1: of rubbed my head. So let's start with the basics.

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Speaker 1: And I know this is going to sound incredibly basic,

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Speaker 1: but we have to build a foundation before we can

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Speaker 1: start talking about the components. So electronics are all about

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Speaker 1: leveraging electricity. Not a big surprise, you're you're leveraging electricity

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Speaker 1: in order to do something to accomplish something like a

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Speaker 1: radio is meant to receive and amplify radio signals and

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Speaker 1: and convert them into acoustic signal so that you can

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Speaker 1: actually hear them. That that's a simple example. A flashlight

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Speaker 1: is meant to channel electricity to end up powering a

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Speaker 1: light bulb, which is essentially a resistor. We will talk

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Speaker 1: about those that heats up. We're talking about a basic

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Speaker 1: incandescent light bulb here, Um and gives off light as

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Speaker 1: a result. That's your basic use of that kind of electronics.

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Speaker 1: So we're gonna talk about how electronics control electricity. These

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Speaker 1: basic components are all used to do that so that

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Speaker 1: you can accomplish whatever the goal of your electronic device is. Now,

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Speaker 1: most electronic devices have lots and lots of different components

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Speaker 1: to them, sometimes worked in various configurations, whether they're in

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Speaker 1: series or in parallel. I'm not going to get into

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Speaker 1: all all of that because that's beyond what I really

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Speaker 1: wanted to focus on in this episode. Instead, in this episode,

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Speaker 1: I want to talk about the very basic components and

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Speaker 1: what they are intended to do. These are the things

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Speaker 1: that make up the circuits that you would see in

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Speaker 1: physical circuitry. So if you ever have, uh, you know,

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Speaker 1: an old electronic device and you were to take it

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Speaker 1: apart and you saw all these little weird do dads

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Speaker 1: on a circuit board, I'm gonna tell you what those

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Speaker 1: do dads do. Dad. Alright, So first we describe an

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Speaker 1: electronics materials is having electrons that fall into certain energy

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Speaker 1: bands or electronic bands. Now, the two important ones that

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Speaker 1: to talk about are the valence band and the conduction band.

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Speaker 1: Electrons and the conduction band are able to move freely

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Speaker 1: through the material in question, assuming the conduction band isn't

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Speaker 1: totally full. You can think of it kind of like

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Speaker 1: a think of it like a nightclub. It's a nightclub

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Speaker 1: that's maybe you know, full, so you can still move

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Speaker 1: through it freely. Now that nightclubs packed, you're not going anywhere,

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Speaker 1: so there has to be you know, almost but not

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Speaker 1: quite full for you to be able to move around.

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Speaker 1: That's the conduction band. That's the basics of electrical conductivity. UH.

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Speaker 1: Whereas the valance band is kind of this um this

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Speaker 1: this basic energy level, and there is a gap between

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Speaker 1: the valence band and the conduction band. UH. It is

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Speaker 1: called the band gap. And depending upon the material, that

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Speaker 1: band gap will be of a certain size, and in

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Speaker 1: some cases the gap is insurmountable. You cannot get electrons

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Speaker 1: from the valence band into the conductance band, and you

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Speaker 1: cannot get them to flow, at least not under normal

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Speaker 1: operating circumstances. So in that sense, think of you've got

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Speaker 1: a like a holding room before you can get into

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Speaker 1: the nightclub, and the the doorway going into the nightclub

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Speaker 1: has got a big old bouncer and that a goal

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Speaker 1: bouncers not letting anyone through. That's your band gap. You

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Speaker 1: cannot there's no one even collectively all of you working together,

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Speaker 1: you're not gonna be able to budge that bouncer. That

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Speaker 1: would be as if you were in a non conducting

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Speaker 1: material and I'll get into more of that later. Whereas

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Speaker 1: if you're in a room where there's a wide open

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Speaker 1: door and you're allowed to go through as long as

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Speaker 1: someone else is coming in, that would mean that you

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Speaker 1: could flow through properly. You've got you got electrical electrical

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Speaker 1: conductivity going on there, and I'll talk more about that

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Speaker 1: in a second. I realized this analogy isn't perfect, but

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Speaker 1: I'm just trying to simplify things for those who haven't

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Speaker 1: really taken this kind of class in physics. So a

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Speaker 1: large gap would represent a great deal of energy needed

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Speaker 1: to move electrons from the valence band to the conductance band,

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Speaker 1: and sometimes that gap is so large as to be

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Speaker 1: impossible to cross again under normal operating conditions. So let's

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Speaker 1: look at the basic materials that we talk about in electronics, conductors, insulators,

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Speaker 1: and semiconductors. Pretty simple to understand. Conductors have high electrical conductivity.

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Speaker 1: That means they facilitate the flow of electrons. Uh. They

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Speaker 1: have a nearly full but not completely full conduction band.

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Speaker 1: Electrons can move freely through this material in response to

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Speaker 1: an electric field applied to that material. So you apply

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Speaker 1: an electrical field to this material, it will then allow

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Speaker 1: electrons to flow through freely. This is the stuff that

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Speaker 1: moves electrons from point A to point B. You apply

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Speaker 1: a voltage across it, you get electrons to flow. That's current,

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Speaker 1: Although technically current flows from positive to negative as opposed

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Speaker 1: to the flow of electrons, which is from negative to positive.

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Speaker 1: We can thank lots of early UH thinkers for that confusion.

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Speaker 1: So current flow and electron flow are in opposite to actions.

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Speaker 1: Thank you, Benjamin Franklin. Uh. Alright, So then you've got insulators.

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Speaker 1: These do not have electrons within the conduction band or

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Speaker 1: they have a full conduction band, so again no room

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Speaker 1: for electrons to move around, so there are no free electrons.

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Speaker 1: They impede the flow of electrons through that material, and

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Speaker 1: most solids fall into this category. Metals are UH an exception,

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Speaker 1: but most solids are insulators. So at normal operating parameters,

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Speaker 1: you wouldn't be able to apply a strong enough electric

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Speaker 1: field to make them conduct electricity. So you could apply

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Speaker 1: an electric field to these things, but it wouldn't be

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Speaker 1: able to jump that gap between the valence band and

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Speaker 1: the conductance band, so it would just stop. You wouldn't

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Speaker 1: have any electrical flow through that at all. So we

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Speaker 1: use insulators for things like insulation on wires where we

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Speaker 1: wrapped the wires in that to help prevent leakage or interference, because,

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Speaker 1: as we've talked about many times on this show, the

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Speaker 1: flow of electricity is also very closely related to magnetism

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Speaker 1: and vice versa. So you have to be able to

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Speaker 1: limit interference between different wires if you don't want there

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Speaker 1: to be that interaction obviously, otherwise you can end up

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Speaker 1: causing shorts, which is when you have an unintended connection

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Speaker 1: between two different elements of a circuit and it allows

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Speaker 1: electricity to pass from one to the other, almost like

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Speaker 1: you think of it like a short cut, you know,

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Speaker 1: when we say an electrical short and it means that

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Speaker 1: the device itself will not work properly because the electricity

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Speaker 1: is not flowing through the pathway you had intended it

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Speaker 1: to go in. All right, then we've got semi conductors,

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Speaker 1: and we'll talk more about them a little bit later,

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Speaker 1: but in general, semi conductors have an almost empty conduction

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Speaker 1: band and an almost full valence band, and the band

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Speaker 1: gap is relatively narrow. So if you don't apply a

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Speaker 1: strong enough electric field at as an insulator, but when

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Speaker 1: you apply the right amount of energy and electric field,

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Speaker 1: it will allow electrons jump from the valance band to

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Speaker 1: the conductor band and move freely within the material. You

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Speaker 1: do this by doping the material, which is when you

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Speaker 1: insert impurities into the semiconductor on purpose. Doping a semiconductor,

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Speaker 1: which is all about introducing impurities specifically at at predetermined levels,

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Speaker 1: will determine the energy levels required to do this, and

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Speaker 1: that's the basis for slid state electronics. We'll get into

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Speaker 1: more about semiconductors towards the end of this. And we

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Speaker 1: also have to remember voltage and current, something that I

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Speaker 1: always have trouble remembering. So voltage is a lot like

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Speaker 1: water pressure, all right. That's that's the the amount of

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Speaker 1: electrical pressure being applied, and the higher the voltage, the

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Speaker 1: more electrons want to move from the concentration of electrons

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Speaker 1: to the or positive side. Now, the actual flow of

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Speaker 1: electricity is the current, so they are related but not

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Speaker 1: the same thing. So voltage and current, and then you

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Speaker 1: multiply those two dependent together and you get the power.

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Speaker 1: So voltage times current equals power. Alright, So those are

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Speaker 1: your basics. Now we're gonna go through and talk about

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Speaker 1: the very individual components and what they do. So first

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Speaker 1: we have resistors. Resistor does pretty much what it sounds

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Speaker 1: like it does. It resists but does not halt the

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Speaker 1: flow of electricity. I'm gonna talk a lot about electricity

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Speaker 1: in terms of water because it is a useful analogy,

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Speaker 1: and it's also very common to talk about the similarities

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Speaker 1: between electricity flowing and water flowing when you're discussing these components.

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Speaker 1: So let's say that you have two different pipes. You've

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Speaker 1: got a brand spanking new pipe. It's shiny and beautiful

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Speaker 1: and free from any any irregularities, and it allows water

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Speaker 1: to flow through with a minimum of resistance. That water

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Speaker 1: is just flowing right through easily. You've got a second, old,

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Speaker 1: gnarly pipe, and this one's got calcium build up in it.

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Speaker 1: They're all these bumps and stuff on the inside. So

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Speaker 1: water actually encounters resistance friction, if you will, as it's

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Speaker 1: flowing through, and it does not flow through as easily.

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Speaker 1: Resistors are like that old gnarly pipe, and they are

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Speaker 1: invented on purpose for specific reasons. So why would you

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Speaker 1: want to have an electronic component that actually slows down

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Speaker 1: or impedes the flow of electricity for some reason. Well,

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Speaker 1: sometimes you have to limit the amount of electricity that

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Speaker 1: can flow through part of a circuit within a given

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Speaker 1: amount of time, sort of like how a faucet going

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Speaker 1: back to water, how fauce it can limit how much

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Speaker 1: water can flow through your water pipes into your sink.

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Speaker 1: So you wouldn't want just an on off switch for

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Speaker 1: the water coming into your home. That water is at

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Speaker 1: a much higher pressure, you know, it's it's a higher

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Speaker 1: pressure to deliver the water to your house. And if

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Speaker 1: all you had wasn't on off switch and you flipped it,

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Speaker 1: you would have water blasting through the pipe according to

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Speaker 1: the amount of pressure that was built up behind it.

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Speaker 1: That'd be a little bit nerving, especially if you just

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Speaker 1: wanted to have a nice frosty glass water. So you

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Speaker 1: want to have some sort of limiter on that to

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Speaker 1: control the amount of water that's or the pressure of

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Speaker 1: the water that's coming in. So resistors reduced the amount

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Speaker 1: of voltage placed on other electronic components within a circuit

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Speaker 1: by restricting the amount of current that can flow through

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Speaker 1: the resistor. The reason why this is important is that

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Speaker 1: we cannot create a battery for every single type of

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Speaker 1: electronic device that's out there. It's not practical. So batteries,

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Speaker 1: different batteries, Different types of batteries have different voltages. So

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Speaker 1: you could, in theory, develop a battery specifically for a

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Speaker 1: particular type of electronic device that would not require resistors

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Speaker 1: because the battery is providing exactly the voltage needed for

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Speaker 1: whatever electronic components are in net. But it's not practical

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Speaker 1: to do that for everything. We want standardized batteries, and

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Speaker 1: then we use things like resistors to help control the

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Speaker 1: voltage in those electronic components so that the right amount

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Speaker 1: of voltage is applied to those specific parts of the

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Speaker 1: electronic circuit, rather than having to have a billion different

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Speaker 1: types of batteries. That would not be practical. So there

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Speaker 1: are many different types of resistors designed to work on

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Speaker 1: specific amounts of electrical power. Now, some have changeable resistor

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Speaker 1: values dependent upon the amount of voltage placed across them.

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Speaker 1: They're called nonlinear or voltage dependent resistors. Resistor values can

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Speaker 1: also change when the temperature of the resistor changes UH.

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Speaker 1: Different types of resistors do this. Some can also be

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Speaker 1: mechanically adjusted. So it all depends upon what you need

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Speaker 1: the resistor for and why what you needed to do.

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Speaker 1: That's what would determine which type of resistor you would use.

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Speaker 1: The unit of measurement for a resistor is the ohm

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Speaker 1: oh h M. Resistor values are ten percent apart from

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Speaker 1: each other, and resistors are color coded with bands of

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Speaker 1: color or rings of color. So the first ring represents

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Speaker 1: the first digit of the resistors value. So what you

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Speaker 1: would do is you would look at the first ring,

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Speaker 1: whatever color it was, you would cross reference that with

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Speaker 1: the with a color UH index, and it would tell

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Speaker 1: you what the value of the resistor is for the

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Speaker 1: first digit. The second ring tells you the value of

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Speaker 1: the second digit. So then you've got the two UH

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Speaker 1: the two digits that are involved. The third tells you

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Speaker 1: the power of ten to multiply by, so it might

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Speaker 1: be ten thousand, and then you would multiply. Let's say

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Speaker 1: that your first two digits are a twenty two and

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Speaker 1: a seven, and you would multiply that by ten thousand.

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Speaker 1: You have twenty seven thousand poems there, and the fourth

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Speaker 1: ring would tell you the tolerance of the resistor plus

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Speaker 1: or minus whatever percentage. Uh So, the physical size of

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Speaker 1: the resistor and the amount of power it can handle

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Speaker 1: tends to be proportional. So in other words, the larger

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Speaker 1: the resistor, the more power it can handle. In general.

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Speaker 1: So those are resistors covers that basic component. Now let's

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Speaker 1: move on to capacitors. Alright. So capacitors are similar to

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Speaker 1: batteries and that it's a means of storing electrical energy,

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Speaker 1: but unlike batteries, instead of creating an a uh, electrical

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Speaker 1: flow through a chemical reaction that is steady the entire

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Speaker 1: time it is designed to release a it's it's entire

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Speaker 1: stored electrical charge all at once. So let's say they've

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Speaker 1: got two leads of a capacitor. You have a difference

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Speaker 1: in voltage across these two leads. That's when a capacitor

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Speaker 1: is charged. So one lead has a greater build up

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Speaker 1: of electrons than the other lead does. Uh. Now, if

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Speaker 1: you were to connect the leads together, you would short them.

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Speaker 1: You would have a discharge of that capacitor and the

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Speaker 1: voltage would equalize across the two, so you get a

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Speaker 1: release of a quick burst of electricity. So capacitors can

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Speaker 1: pass alternating current freely. A C current will just pass

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Speaker 1: through a capacitor as if it were not really there.

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Speaker 1: Direct current, however, will charge a capacitor. It will have

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Speaker 1: that build up of electrons on one side, while the

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Speaker 1: other side doesn't get that build up of electrons, and

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Speaker 1: then you have that difference in voltage. Alternating current just

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Speaker 1: will pass back and forth through it without any problems.

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Speaker 1: So capacitors contain the same fundamental parts. You have at

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Speaker 1: least two conductive plates separated by a non conductive material.

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Speaker 1: That's the dilector. The amount of charge held by capacitor

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Speaker 1: is measured in units called faret's. But a faret is

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Speaker 1: a large amount of capacitance, so large that you don't

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Speaker 1: really ever talk about a ferret. Instead we end up

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Speaker 1: talking about micro farets, which are about a well, which

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Speaker 1: are one million of a ferret, so much smaller. Faret,

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Speaker 1: by the way, not ferret, two different things. Nice Mormot

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Speaker 1: capacitance is dependent upon surface area, so it's directly proportional

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Speaker 1: to the surface area of those leads. Those those capacity plates. Um.

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Speaker 1: It is indirectly proportional to the distance between the plates.

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Speaker 1: So the greater the distance between the plates, the lower

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Speaker 1: the capacitance. Uh. It's also uh dependent upon the dielectric

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Speaker 1: constant of the insulating material. And they are used for

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Speaker 1: things that need a quick release of electricity rather than

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Speaker 1: a steady flow. So, for example, a tradition all flash

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Speaker 1: on a camera. So you've got an old camera and

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Speaker 1: you've got the the the flash, Uh, you know it

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Speaker 1: bursts in this quick burst of light. Well, it needs

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Speaker 1: that quick It needs access to a quick burst of

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Speaker 1: electricity in order to do that, and that's what capacitors

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Speaker 1: are good for. And it takes some time for the

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00:18:18,480 --> 00:18:20,719
Speaker 1: capacitors to build up the charge again so it can

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Speaker 1: do it another time. That's sort of you know, if

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Speaker 1: you're using the old ones, you hear that noise. It's

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Speaker 1: the the discharge and then charging of the capacitors that

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Speaker 1: require you to take a moment between taking pictures with

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Speaker 1: those old style camera flashes. Now obviously newer ones used

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Speaker 1: different a different approach, but you often have capacitors that

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Speaker 1: actually provide the electricity for those. Now, the voltage of

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Speaker 1: a capacitor cannot change instantly, it's important to remember, and

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Speaker 1: quick voltage changes in a capacitor produced large current changes.

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Speaker 1: Capacitor store energy in an electric field. Now, the reason

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Speaker 1: I mentioned all that is because we're now going to

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Speaker 1: talk about inductors, and inductors are kind of, um the

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Speaker 1: opposite of capacitors, or really maybe not even opposite is

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Speaker 1: the right way of saying it. In many ways that

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Speaker 1: they behave in opposite ways than capacitors do, but we'll

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Speaker 1: get to that. So basically, an inductor at its most

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Speaker 1: basic level is a coil of wires, so sometimes we

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Speaker 1: just call them coils and not inductors. Uh. They deal

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Speaker 1: with what is the electrical equivalent of momentum. So if

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Speaker 1: you're familiar with momentum, essentially this is that idea that

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Speaker 1: you get a you know, objects in motion tend to

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Speaker 1: stay in motion. So let's say you've got a large

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Speaker 1: mass moving at a particular velocity. It has a certain

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Speaker 1: amount of momentum, and you have to overcome that momentum

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Speaker 1: to slow down and stop that uh, that that mass.

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Speaker 1: So it's the same type of thing with inductors, except

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Speaker 1: we're talking about the electrical equivalent of momentum. We're talking

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Speaker 1: about the flow of electricity. So again going back to

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Speaker 1: the water analogy, Let's say that you've got a water hose,

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Speaker 1: a really long one, several hundred feet long, and you've

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Speaker 1: coiled it up so it's in a nice long coil

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Speaker 1: and it's filled with water. There are gallons of water

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Speaker 1: inside this hose, and the end of the hose is

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Speaker 1: tilted at such an angle so the water is not

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Speaker 1: just flowing right out. You put a plunger into the

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Speaker 1: other end and you start to press on the plunger

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Speaker 1: to push the water out. Now, all of that water

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Speaker 1: is not just going to simultaneously start to move together.

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Speaker 1: It actually is going to take some time for the

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Speaker 1: pressure you are applying to exert enough force to push

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Speaker 1: the water out to overcome the inertia within that coil

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Speaker 1: of water hose. And once you get that water coming

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Speaker 1: out at the speed at which it can come out

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Speaker 1: and you let go of the plunger, the plunger is

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Speaker 1: going to continue going down that tube because of inertia.

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Speaker 1: That's the same sort of thing with inductors, except instead

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Speaker 1: of water, we're talking about electricity. So coils of wire

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Speaker 1: will pass d C current but will block a C current.

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Speaker 1: So in other words, direct current can flow through an inductor,

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Speaker 1: but alternating current would be blocked because it cannot flow

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Speaker 1: the opposite way through the coil. So that makes it

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Speaker 1: the opposite of capacitors. Remember, capacitors would pass alternating current

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Speaker 1: that can flow straight through, but would block direct current.

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Speaker 1: Direct current would charge a capacitor a capacitor, but could

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Speaker 1: not just flow through the capacitor. In this case, direct

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00:21:47,520 --> 00:21:51,360
Speaker 1: current can flow through an inductor, but a c alternating

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00:21:51,400 --> 00:21:55,359
Speaker 1: current would be blocked. The standard unit of inductance is

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Speaker 1: the henry. I wish I could tell you why, but

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Speaker 1: I honestly don't know. I'm sure some of you out there,

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Speaker 1: you electricians, are very familiar with the reason why and

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Speaker 1: could tell me and feel free to I I honestly

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Speaker 1: do not off hand. No, the inductance of a coil

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Speaker 1: is indirectly proportional to the length of the coil, but

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00:22:16,040 --> 00:22:20,679
Speaker 1: directly proportional to the cross sectional area of the wire, So,

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00:22:20,720 --> 00:22:23,880
Speaker 1: in other words, the gauge of the wire is important here.

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Speaker 1: It's also proportional to the square of the number of

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Speaker 1: turns in the coil, and it's directly proportional to the

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00:22:30,080 --> 00:22:33,840
Speaker 1: permeability of the core material. Now the core is whatever

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Speaker 1: this coil is wrapped around. Now it could be wrapped

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Speaker 1: around air, or it could be wrapped around something like iron,

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Speaker 1: which is incredibly effective. So those are that's what we're

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00:22:43,240 --> 00:22:45,919
Speaker 1: talking about with the cords, whatever the wire or is

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Speaker 1: coiled around. So when current first starts flowing into the coil,

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Speaker 1: the coil wants to build up a magnetic field. We've

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Speaker 1: talked about this again and again that you start running

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Speaker 1: electricity through a coil of wire that's coiled around like

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Speaker 1: an iron core, like a nail, and you start to

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Speaker 1: you create an electro magnet. Well, once that field is built.

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Speaker 1: While while the magnetic field is building, the coil inhibits

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Speaker 1: the flow of current through the wire. But once the

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Speaker 1: field is built, current can flow normally through the wire.

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Speaker 1: So if you were to have an inductor hooked up

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Speaker 1: to a light bulb, let's say and you flip a

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Speaker 1: switch so that you know, technically in an electronics would

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Speaker 1: say that you close the switch, so you have created

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Speaker 1: a closed path so electrons can flow through. The electrons

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Speaker 1: would flow through the inductor, which would start to build

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Speaker 1: up a magnetic field. So at first you would get

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Speaker 1: the light bulb coming on, then it would start to

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Speaker 1: dim a bit because as that magnetic field is getting

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Speaker 1: built up the lightbulb, you know, the electricity would be

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00:23:52,800 --> 00:23:55,320
Speaker 1: limited to the light bulb. It would actually act as

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Speaker 1: sort of resistor, and the light bulb would start to

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Speaker 1: get dimmer. But then eventually then that magnetic field would

390
00:24:01,400 --> 00:24:03,720
Speaker 1: get charged up as much as it can because it's

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Speaker 1: direct current, not alternating current, and you would reach a

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Speaker 1: level where it was stabilized. Current would flow fine. At

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Speaker 1: that point, you can actually turn off the switch, you

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Speaker 1: can open it. In other words, the magnetic field around

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Speaker 1: the coil would keep current flowing through the coil until

396
00:24:23,840 --> 00:24:27,040
Speaker 1: that magnetic field collapsed. So even though you turn the

397
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Speaker 1: switch to off, because you have an inductor, that lightbulb

398
00:24:31,359 --> 00:24:35,520
Speaker 1: would stay lit until the magnetic field and the inductor collapsed,

399
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Speaker 1: in which case it would stop inducing current to flow

400
00:24:38,560 --> 00:24:42,760
Speaker 1: through and the light bulb would go off. So the

401
00:24:42,840 --> 00:24:45,959
Speaker 1: experience you would have is turn the switch on, light

402
00:24:46,040 --> 00:24:49,640
Speaker 1: bulb comes on, light bulb starts to get dim, light

403
00:24:49,680 --> 00:24:52,640
Speaker 1: bulb gets bright again, You turn the switch off, lightbulb

404
00:24:52,680 --> 00:24:55,560
Speaker 1: stays lit for a while, and then turns off. That's

405
00:24:55,560 --> 00:24:59,159
Speaker 1: what it would look like to you, So pretty interesting

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00:24:59,240 --> 00:25:02,919
Speaker 1: to me. Now. So, an inductor stores energy in its

407
00:25:03,000 --> 00:25:06,240
Speaker 1: magnetic field, and it tends to resist any change in

408
00:25:06,280 --> 00:25:09,960
Speaker 1: the amount of current flowing through it, thus making it

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00:25:10,040 --> 00:25:13,520
Speaker 1: different from capacitors. Because capacitors store things an electric field,

410
00:25:14,040 --> 00:25:19,080
Speaker 1: inductor store things energy, not just things. Capacitor store energy

411
00:25:19,119 --> 00:25:22,400
Speaker 1: and electric fields, and inductor store energy and magnetic fields.

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00:25:23,240 --> 00:25:28,760
Speaker 1: And capacitors resist changes to voltage, whereas inductors resist changes

413
00:25:28,800 --> 00:25:33,119
Speaker 1: to current. So really interesting about that. So because of

414
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Speaker 1: this relationship between inductors and capacitors, these two different components

415
00:25:38,040 --> 00:25:42,719
Speaker 1: are sometimes referred together as dual components because they they

416
00:25:42,760 --> 00:25:46,399
Speaker 1: are opposites that complement one another. The current in an

417
00:25:46,440 --> 00:25:49,840
Speaker 1: inductor cannot change instantly the quick current changes produced the

418
00:25:49,920 --> 00:25:53,360
Speaker 1: large voltage, and inductors store their energy in those magnetic fields.

419
00:25:53,400 --> 00:25:56,639
Speaker 1: That's what sets them opposite of capacitors, because they are

420
00:25:56,680 --> 00:25:59,920
Speaker 1: all the opposite of those things. And you might wonder

421
00:26:00,119 --> 00:26:02,520
Speaker 1: what are inductors used for. I mean, that lightbulb example

422
00:26:02,560 --> 00:26:06,200
Speaker 1: seems kind of crazy. Well, they're used for lots of stuff.

423
00:26:06,200 --> 00:26:09,400
Speaker 1: For example, if you've ever gone to uh, like traffic

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00:26:09,480 --> 00:26:12,360
Speaker 1: lights that are that respond to the presence of vehicles.

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00:26:12,800 --> 00:26:16,520
Speaker 1: Most of those are using inductors. So underneath the pavement

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00:26:16,920 --> 00:26:19,720
Speaker 1: where you're driving on top of you know, there are

427
00:26:20,040 --> 00:26:25,040
Speaker 1: giant coils of wire, and when you stop your car

428
00:26:25,200 --> 00:26:28,560
Speaker 1: at a stoplight that has one of these systems, your

429
00:26:28,560 --> 00:26:32,280
Speaker 1: car starts to act as the core for that inductor loop.

430
00:26:32,320 --> 00:26:35,359
Speaker 1: You've got this massive amount of steel that's right there

431
00:26:35,440 --> 00:26:39,760
Speaker 1: that affects the inductance of the that cable. You have

432
00:26:39,800 --> 00:26:42,720
Speaker 1: a meter attached to the cable that measures the inductance.

433
00:26:43,560 --> 00:26:46,960
Speaker 1: So when it measures a change in inductance, that meter

434
00:26:47,160 --> 00:26:51,480
Speaker 1: knows there's a vehicle at that location and sends that

435
00:26:51,560 --> 00:26:55,479
Speaker 1: information to the control unit for the traffic system and

436
00:26:55,520 --> 00:26:58,760
Speaker 1: thus changes the traffic cycle so that you get a

437
00:26:58,840 --> 00:27:01,439
Speaker 1: green light faster. So if you're ever at one of

438
00:27:01,440 --> 00:27:06,560
Speaker 1: those intersections where the the light cycles depend heavily upon

439
00:27:06,640 --> 00:27:09,440
Speaker 1: whether or not there are cars present at the intersection,

440
00:27:10,280 --> 00:27:13,840
Speaker 1: that's generally speaking, what is happening. You've got these inductors.

441
00:27:13,880 --> 00:27:17,359
Speaker 1: The inductance changes, sends the message to the meter, or

442
00:27:17,440 --> 00:27:20,080
Speaker 1: rather the meter detects the inductor the change in inductance

443
00:27:20,520 --> 00:27:23,840
Speaker 1: and then sends that onto the traffic control system that

444
00:27:23,960 --> 00:27:27,040
Speaker 1: will then, at least in theory, get you on your

445
00:27:27,040 --> 00:27:32,600
Speaker 1: way a little faster. So that's inductors. Now let's take

446
00:27:32,640 --> 00:27:37,160
Speaker 1: a look at transformers, which are more than meets the eye.

447
00:27:37,840 --> 00:27:40,159
Speaker 1: So I'm not talking about autobots in Decepticons, as much

448
00:27:40,200 --> 00:27:42,960
Speaker 1: as I would love to do that, instead of talking

449
00:27:43,000 --> 00:27:46,360
Speaker 1: about the basic electronic component. So let's say you've got

450
00:27:46,400 --> 00:27:50,520
Speaker 1: a single core, like like that iron nail. Let's say

451
00:27:51,560 --> 00:27:55,520
Speaker 1: and you put multiple coils of wire over this same

452
00:27:55,600 --> 00:27:59,200
Speaker 1: iron core, and then you force a DC current through

453
00:27:59,400 --> 00:28:01,960
Speaker 1: one of those coils of wire, not all of them,

454
00:28:02,119 --> 00:28:05,719
Speaker 1: just one. Now, as that current charges, it will induce

455
00:28:05,760 --> 00:28:08,639
Speaker 1: current to flow through the other coils wrapped around that

456
00:28:08,800 --> 00:28:13,679
Speaker 1: same core, and constantly changing the voltage of that primary coil.

457
00:28:14,040 --> 00:28:16,119
Speaker 1: The one that you've got attached to some sort of

458
00:28:16,200 --> 00:28:20,520
Speaker 1: voltage generator will cause currents that change in a similar

459
00:28:20,560 --> 00:28:24,080
Speaker 1: fashion in the other coils. Now, if the other coils

460
00:28:24,080 --> 00:28:27,600
Speaker 1: have more loops than the primary coil, the voltage will

461
00:28:27,640 --> 00:28:30,639
Speaker 1: be greater, but the current will be lower. I'll explain

462
00:28:30,680 --> 00:28:32,640
Speaker 1: that in the second. So let's say we've got we'll

463
00:28:32,680 --> 00:28:35,440
Speaker 1: make it really simple. We'll just do two coils. Let's

464
00:28:35,440 --> 00:28:38,040
Speaker 1: say we've got an iron core and we've got a

465
00:28:38,080 --> 00:28:42,200
Speaker 1: primary wire coiled around it ten times, and we have

466
00:28:42,240 --> 00:28:45,200
Speaker 1: a second wire coiled in the same direction around that

467
00:28:45,280 --> 00:28:49,120
Speaker 1: iron core, but it is coiled twenty times, and we

468
00:28:49,200 --> 00:28:53,560
Speaker 1: apply a varying voltage across the primary wire. The voltage

469
00:28:53,560 --> 00:28:55,920
Speaker 1: across the second wire will be twice as much because

470
00:28:55,920 --> 00:28:59,480
Speaker 1: there are twice as many coils, but the current will

471
00:28:59,520 --> 00:29:03,440
Speaker 1: be as much as that in the primary coil. And

472
00:29:03,480 --> 00:29:06,920
Speaker 1: that's because you have to conserve power. You cannot create

473
00:29:07,000 --> 00:29:09,840
Speaker 1: or destroy power. You have to conserve it. And power,

474
00:29:09,880 --> 00:29:13,360
Speaker 1: like I said earlier, is equal to voltage times current.

475
00:29:13,680 --> 00:29:16,760
Speaker 1: So if we double the voltage, but ultimately the power

476
00:29:16,800 --> 00:29:18,959
Speaker 1: in the secondary coil has to be the same as

477
00:29:19,000 --> 00:29:22,640
Speaker 1: the primary coil. The only way to address that is

478
00:29:22,680 --> 00:29:28,040
Speaker 1: to have the current. So that's you know, that's what happens.

479
00:29:28,080 --> 00:29:30,960
Speaker 1: So if the second coil is coiled in the same

480
00:29:30,960 --> 00:29:33,640
Speaker 1: direction as the primary, like I was saying before, the

481
00:29:33,760 --> 00:29:37,360
Speaker 1: voltage is in the same polarity as that of the

482
00:29:37,440 --> 00:29:41,040
Speaker 1: generator the primary coil. If the second coil is coiled

483
00:29:41,040 --> 00:29:44,680
Speaker 1: in the opposite direction of the primary coil, then the

484
00:29:44,760 --> 00:29:48,640
Speaker 1: voltage is in the opposite polarity from the primary coil.

485
00:29:49,080 --> 00:29:52,680
Speaker 1: Polarity is really important but also pretty complicated, So I'll

486
00:29:52,680 --> 00:29:57,520
Speaker 1: probably spend another episode to explain that concept because it's

487
00:29:57,640 --> 00:30:02,400
Speaker 1: really a bit much to go into right now. But anyway,

488
00:30:02,440 --> 00:30:07,160
Speaker 1: this is the basics for power transmission using alternating current.

489
00:30:07,200 --> 00:30:11,640
Speaker 1: It's the reason why we have alternating current distributing our

490
00:30:11,680 --> 00:30:14,920
Speaker 1: power instead of direct current. So, and that old Tesla

491
00:30:15,120 --> 00:30:20,840
Speaker 1: versus Edison argument, really i should say Westinghouse versus Edison argument,

492
00:30:21,400 --> 00:30:24,960
Speaker 1: where Edison was saying direct current was best and Westinghouse

493
00:30:25,040 --> 00:30:28,760
Speaker 1: was saying no alternating current was best. The things that

494
00:30:28,840 --> 00:30:31,760
Speaker 1: let alternating current win out over direct current, or that

495
00:30:32,280 --> 00:30:37,480
Speaker 1: using transformers you could boost the voltage to huge high

496
00:30:37,600 --> 00:30:41,480
Speaker 1: voltage numbers, which were great for power transmission. You could

497
00:30:41,480 --> 00:30:46,560
Speaker 1: transmit over vast distances using high voltage wires, and then

498
00:30:46,600 --> 00:30:49,400
Speaker 1: you would use other transformers on the opposite end to

499
00:30:49,600 --> 00:30:53,040
Speaker 1: step down the voltage until you reach the level that

500
00:30:53,120 --> 00:30:55,200
Speaker 1: was safe for homes, which in the United States is

501
00:30:55,240 --> 00:30:58,640
Speaker 1: two forty volts. Uh. Now, keep in mind that when

502
00:30:58,680 --> 00:31:01,800
Speaker 1: you're talking about transmiss voltages, it could be anywhere between

503
00:31:01,800 --> 00:31:05,880
Speaker 1: a hundred fifty five thousand to seven sixty thousand volts.

504
00:31:05,920 --> 00:31:09,400
Speaker 1: So we're talking huge differences here, and it's all because

505
00:31:09,520 --> 00:31:13,520
Speaker 1: you could use this basic element of electronics with these

506
00:31:14,120 --> 00:31:17,600
Speaker 1: transformers to step up or step down the voltage simply

507
00:31:17,640 --> 00:31:23,520
Speaker 1: by using different coils along a core, So that was

508
00:31:23,560 --> 00:31:27,200
Speaker 1: incredibly useful. You could end up transmitting power over great distances.

509
00:31:27,280 --> 00:31:30,880
Speaker 1: Direct current, however, is very different. It is most efficient

510
00:31:31,040 --> 00:31:33,959
Speaker 1: if it is close to whatever the load is on

511
00:31:34,000 --> 00:31:37,960
Speaker 1: the line. So the load is whatever the electricity is

512
00:31:38,000 --> 00:31:40,520
Speaker 1: meant to power. So in the case of homes, you

513
00:31:40,560 --> 00:31:43,960
Speaker 1: would want the power plant to be relatively close to

514
00:31:43,960 --> 00:31:47,480
Speaker 1: the homes that are receiving electricity. If you were using

515
00:31:47,480 --> 00:31:50,960
Speaker 1: direct current, um this is you know, it would be

516
00:31:50,960 --> 00:31:55,120
Speaker 1: incredibly useful to have direct current powering our homes because

517
00:31:55,160 --> 00:31:59,120
Speaker 1: most of the stuff we have relies on direct current.

518
00:32:00,120 --> 00:32:03,560
Speaker 1: It actually has to convert the alternating current that comes

519
00:32:03,600 --> 00:32:07,600
Speaker 1: to the house into direct current. You have these converters

520
00:32:07,600 --> 00:32:10,080
Speaker 1: that are part of the electronics that allow it to

521
00:32:10,160 --> 00:32:14,440
Speaker 1: do that. If you had direct current being uh supplied

522
00:32:14,480 --> 00:32:17,080
Speaker 1: directly to your house, you wouldn't need the conversion part

523
00:32:17,240 --> 00:32:20,640
Speaker 1: of those devices. However, you wouldn't be able to transmit

524
00:32:20,640 --> 00:32:23,800
Speaker 1: it over great distances like you can with alternating current.

525
00:32:24,320 --> 00:32:27,240
Speaker 1: So in case you're wondering about the power grades in

526
00:32:27,240 --> 00:32:30,360
Speaker 1: the United States, we I mentioned that you have those

527
00:32:30,440 --> 00:32:33,920
Speaker 1: those high voltage lines that are carrying between a HUDD

528
00:32:33,960 --> 00:32:37,240
Speaker 1: to s hred sixty thousand volts. When you get to

529
00:32:37,720 --> 00:32:41,840
Speaker 1: distribution levels, you step down that voltage to less than

530
00:32:41,880 --> 00:32:45,040
Speaker 1: ten thousand volts typically, and then you get to distribution

531
00:32:45,120 --> 00:32:48,600
Speaker 1: buses that have transformers that reduce it further to seven thousand,

532
00:32:48,640 --> 00:32:51,280
Speaker 1: two hundred volts or less. And then you have the

533
00:32:51,320 --> 00:32:53,760
Speaker 1: homes that are connected to a final transformer that step

534
00:32:53,760 --> 00:32:57,360
Speaker 1: it down again to the voltage of two volts or so.

535
00:32:57,360 --> 00:33:04,680
Speaker 1: So incredibly useful and here at how stuff works. Recently,

536
00:33:04,880 --> 00:33:07,440
Speaker 1: as of the recording of this podcast, we had a

537
00:33:07,560 --> 00:33:12,160
Speaker 1: lovely transformer fire right next to the building we work in,

538
00:33:12,160 --> 00:33:14,920
Speaker 1: which cut power to our part of the building for

539
00:33:15,000 --> 00:33:18,080
Speaker 1: some time. So if you've ever been near a transformer

540
00:33:18,160 --> 00:33:21,600
Speaker 1: when it's blown, it's a pretty spectacular thing. It's usually

541
00:33:21,680 --> 00:33:24,800
Speaker 1: lots of sparks in a really loud bang, and often

542
00:33:24,840 --> 00:33:29,960
Speaker 1: requires the work of dedicated personnel to repair. And it

543
00:33:30,040 --> 00:33:33,280
Speaker 1: does also typically mean that you have a loss of

544
00:33:33,360 --> 00:33:38,760
Speaker 1: power for at least a localized area. Pretty impressive when

545
00:33:38,800 --> 00:33:41,760
Speaker 1: it happens. Luckily, it doesn't happen all that frequently. The

546
00:33:41,880 --> 00:33:45,920
Speaker 1: electrical storms and areas of or times of great use

547
00:33:46,560 --> 00:33:50,880
Speaker 1: can make them more vulnerable. Now let's move on to

548
00:33:51,480 --> 00:33:55,200
Speaker 1: semiconductors and how they are used in electronics. So we've

549
00:33:55,240 --> 00:33:57,760
Speaker 1: got lots of different uses for semiconductors. I'm going to

550
00:33:57,880 --> 00:34:01,600
Speaker 1: talk about two specific ones. There are iodes. Diodes are

551
00:34:01,600 --> 00:34:04,720
Speaker 1: really useful. They allow current to flow in only one direction,

552
00:34:04,760 --> 00:34:07,600
Speaker 1: so it's like a one way channel or a valve.

553
00:34:07,960 --> 00:34:10,520
Speaker 1: So electricity flowing one way is fine, but it cannot

554
00:34:10,560 --> 00:34:14,560
Speaker 1: flow back the other way, and semiconductor doping allows for

555
00:34:14,600 --> 00:34:17,600
Speaker 1: this to happen. Remember I mentioned earlier. Doping is when

556
00:34:17,640 --> 00:34:21,480
Speaker 1: you have introduced impurities into the semiconductor material to give

557
00:34:21,480 --> 00:34:25,920
Speaker 1: it specific UH features. So there are two different types

558
00:34:26,560 --> 00:34:29,440
Speaker 1: that we're going to talk about. There's end type layers

559
00:34:29,520 --> 00:34:31,759
Speaker 1: of semiconductors, so you can think of that as an

560
00:34:31,760 --> 00:34:35,960
Speaker 1: excess of electrons. It has lots of negative electrons that

561
00:34:36,040 --> 00:34:39,319
Speaker 1: are just ready to flow out of there. And then

562
00:34:39,360 --> 00:34:44,120
Speaker 1: you have P type layers and these have electron holes

563
00:34:44,320 --> 00:34:45,840
Speaker 1: or at least you know, in other words, of the

564
00:34:45,840 --> 00:34:50,400
Speaker 1: capacity to take on electrons. So if you pair this together,

565
00:34:50,880 --> 00:34:54,000
Speaker 1: you get what's called a P N diode, which only

566
00:34:54,040 --> 00:34:57,279
Speaker 1: allows electricity to flow in one direction. It can Electrons

567
00:34:57,320 --> 00:35:01,880
Speaker 1: can come through UH and flow to the holes, but

568
00:35:01,920 --> 00:35:05,440
Speaker 1: they can't go the other way, so very useful and

569
00:35:05,520 --> 00:35:08,840
Speaker 1: electronic components where you need to direct the flow of

570
00:35:08,840 --> 00:35:11,840
Speaker 1: electricity along a particular path and prevent it from coming

571
00:35:11,840 --> 00:35:17,360
Speaker 1: back through that pathway. Transistors are another type of semiconductor

572
00:35:17,440 --> 00:35:19,880
Speaker 1: that use a small amount of current to control a

573
00:35:20,040 --> 00:35:24,239
Speaker 1: large amount of current. So while a diode is p n,

574
00:35:25,280 --> 00:35:29,840
Speaker 1: transistors are either p n P or n p n,

575
00:35:30,600 --> 00:35:33,480
Speaker 1: and if you apply an electrical current to the center layer,

576
00:35:33,560 --> 00:35:36,120
Speaker 1: which is also known as the base, electrons will move

577
00:35:36,239 --> 00:35:38,800
Speaker 1: from the N type side to the P type side,

578
00:35:39,080 --> 00:35:41,800
Speaker 1: and that initial small current allows for much larger current

579
00:35:41,800 --> 00:35:44,960
Speaker 1: to flow through the material at that point. So transistors

580
00:35:45,080 --> 00:35:50,440
Speaker 1: act as switches or amplifiers incredibly useful. So when we

581
00:35:50,440 --> 00:35:54,759
Speaker 1: talk about transistors in solid state electronics, these are the

582
00:35:54,800 --> 00:35:59,000
Speaker 1: things that allow us to build logic circuits. And it's

583
00:35:59,040 --> 00:36:03,400
Speaker 1: because we can allow electrons to either flow or prevent

584
00:36:03,440 --> 00:36:07,480
Speaker 1: them from flowing. It's also why things like electron tunneling

585
00:36:07,520 --> 00:36:11,760
Speaker 1: can be such a problem. Electron tunneling is a quantum effect,

586
00:36:12,239 --> 00:36:14,480
Speaker 1: so you can think of an electron as not really

587
00:36:14,480 --> 00:36:19,160
Speaker 1: existing in a specific point in space at any given time,

588
00:36:19,200 --> 00:36:23,160
Speaker 1: but rather having the potential to exist in an area

589
00:36:23,360 --> 00:36:26,560
Speaker 1: of space at any point in time. So think of

590
00:36:26,600 --> 00:36:30,880
Speaker 1: it like a cloud where an electron could be, and

591
00:36:30,960 --> 00:36:34,120
Speaker 1: that cloud covers all the potential places the electron could be,

592
00:36:34,160 --> 00:36:37,000
Speaker 1: and there's different probability for different parts of the cloud.

593
00:36:37,960 --> 00:36:42,640
Speaker 1: If your transistor gates are so small, so narrow, so thin,

594
00:36:42,760 --> 00:36:46,120
Speaker 1: I guess I should say not narrow, that the cloud

595
00:36:46,280 --> 00:36:50,759
Speaker 1: of potential can overlap the transistor gate. That means there

596
00:36:50,840 --> 00:36:54,600
Speaker 1: is the possibility that at some point the electron could

597
00:36:54,600 --> 00:36:57,319
Speaker 1: exist on the other side of the transistor gate, even

598
00:36:57,320 --> 00:37:01,400
Speaker 1: if the gate never opened. And if there's a possibility,

599
00:37:01,520 --> 00:37:04,160
Speaker 1: that means sometimes it does appear on the other side

600
00:37:04,200 --> 00:37:06,200
Speaker 1: of the gate. We call it electron tunneling. It's not

601
00:37:06,400 --> 00:37:09,719
Speaker 1: really tunneling. It's just if there is the possibility that

602
00:37:09,800 --> 00:37:12,080
Speaker 1: could be on the other side, sometimes it is on

603
00:37:12,120 --> 00:37:15,680
Speaker 1: the other side, which means that you cannot actually control

604
00:37:15,719 --> 00:37:18,000
Speaker 1: the flow of electrons. In that case, it would mean

605
00:37:18,040 --> 00:37:21,239
Speaker 1: that your transistors would be ineffective in doing what they're

606
00:37:21,280 --> 00:37:23,080
Speaker 1: supposed to do. They wouldn't really be able to act

607
00:37:23,080 --> 00:37:27,720
Speaker 1: to switches reliably, and you would get errors in your computations.

608
00:37:28,200 --> 00:37:30,879
Speaker 1: It might work most of the time and then only

609
00:37:31,080 --> 00:37:33,719
Speaker 1: some of the time not work. But even then that's problematic,

610
00:37:34,000 --> 00:37:38,239
Speaker 1: which is one of the engineering challenges that transistor designers

611
00:37:38,239 --> 00:37:42,399
Speaker 1: and multi or rather microprocessor designers encounter all the time,

612
00:37:42,520 --> 00:37:46,920
Speaker 1: you know, finding new materials that are better at acting

613
00:37:47,000 --> 00:37:51,200
Speaker 1: as transistors switches, it's a big part of it. And

614
00:37:51,400 --> 00:37:54,799
Speaker 1: coming up with different architectures to really take advantage of

615
00:37:54,880 --> 00:37:58,360
Speaker 1: electron flow is another big part of it, alright. So

616
00:37:58,480 --> 00:38:02,480
Speaker 1: those are the basics, the basic electronic components that you

617
00:38:02,520 --> 00:38:05,719
Speaker 1: can talk about with, you know, if you're looking at

618
00:38:05,719 --> 00:38:08,239
Speaker 1: it from a very high level. Obviously there's tons of

619
00:38:08,239 --> 00:38:10,640
Speaker 1: other stuff that I didn't get into, and some of

620
00:38:10,680 --> 00:38:15,560
Speaker 1: it just requires you to pair up or otherwise put

621
00:38:15,600 --> 00:38:18,200
Speaker 1: into series or parallels some of the components I've mentioned

622
00:38:18,480 --> 00:38:21,560
Speaker 1: to to get whatever effects you want. But those are

623
00:38:21,560 --> 00:38:24,440
Speaker 1: the basics, so when you look at those different components,

624
00:38:24,520 --> 00:38:27,520
Speaker 1: you can remember that this is all about making sure

625
00:38:27,840 --> 00:38:31,440
Speaker 1: that the electrons are behaving in the way that makes

626
00:38:31,480 --> 00:38:35,200
Speaker 1: whatever it is you intend to do possible. I want

627
00:38:35,200 --> 00:38:38,720
Speaker 1: to thank Chris for sending that email in and asking

628
00:38:38,760 --> 00:38:41,720
Speaker 1: about this, because it was fun to cover this this

629
00:38:41,719 --> 00:38:44,400
Speaker 1: this topic again and to really kind of dive in

630
00:38:44,560 --> 00:38:47,360
Speaker 1: more deeply than I had before, and I want to

631
00:38:47,440 --> 00:38:51,560
Speaker 1: encourage you guys to write in and ask about other topics.

632
00:38:51,560 --> 00:38:54,560
Speaker 1: Whether it's a technology or a company or a person,

633
00:38:55,680 --> 00:38:58,160
Speaker 1: or maybe it's someone that you want to have on

634
00:38:58,200 --> 00:39:00,440
Speaker 1: the show, either as a guest host or someone for

635
00:39:00,480 --> 00:39:03,480
Speaker 1: me to interview. Any of that is fine. Please let

636
00:39:03,520 --> 00:39:05,560
Speaker 1: me know, or just feedback in general about the show.

637
00:39:05,600 --> 00:39:07,680
Speaker 1: I would love to hear more from you guys. Sent

638
00:39:07,800 --> 00:39:10,879
Speaker 1: me a message. The email address is tech Stuff at

639
00:39:11,000 --> 00:39:13,760
Speaker 1: how stuff works dot com, or drop me a line

640
00:39:13,800 --> 00:39:16,919
Speaker 1: on Facebook, Twitter, or Tumblr. The handle it all three

641
00:39:16,960 --> 00:39:19,719
Speaker 1: is tech Stuff H s W. And I'll talk to

642
00:39:19,719 --> 00:39:28,480
Speaker 1: you again really soon. For more on this and thousands

643
00:39:28,520 --> 00:39:40,239
Speaker 1: of other topics. Works dot com