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Shmoop! Electrical charge transfer: without it, well this whole internet thing

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wouldn't work very well. What is electricity anyway? Well it charges. Electric [facts on chalkboard]

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field, strawberry field. Playing with sticky tape, haha we've done that. Well I think it's safe to say that electricity

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is important. It's the reason your fridge keeps everything cold. The reason your

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microwave heats up your food, and well yeah, it's the reason you're able to

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watch this video right here. Without electricity we'd probably be

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broadcasting this physics lesson via, smoke signals. All right well what is

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electricity anyway? Don't worry we're not gonna go all the way back to Ben [Ben Franklin flying kite in storm]

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Franklin flying a kite in a storm or anything. But, we need to understand

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what's actually going on when you plug in your hairdryer. I mean we know that

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the end result will be incredible sexiness. But, how does electricity move

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from the wall, to that wire, to the actual motor, fan thingy, there. Well let's take a

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look at an atom. We'll go super basic, the hydrogen atom. Almost all hydrogen has

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one proton and one electron. Well the proton has a positive charge, it's all [hydrogen atom drawing]

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about smiles and motivational posters and the electron here is a real debbie

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downer, because well it has a negative charge. That positive and negative

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difference is called polarity. And the amount of charge in a proton and in an

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electron is equal, even though their polarity is opposite. That amount is

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called the elementary charge. You can't get any smaller than the elementary

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charge and that's as low as it goes. There's never going to be a time when

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just half an electron shows up, or where we'll have to deal with one quarter

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proton. The elementary charge is written as just a little e, like that.[atom with e above] These

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electrical charges either positive or negative are fundamental properties of

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matter, kind of like mass. And you might be wondering where does charge really

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come from and yeah that's a really good question. I hope you come up with an

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answer soon because so far science doesn't have a good explanation. There

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are some ideas out there that are pretty complicated and involve mind-bending

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aspects of quantum mechanics and honestly, just thinking about that stuff [construction man wearing helmet]

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makes me want to find a darkroom and rock gently back and forth. So we're not

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gonna dig into that right now. And just like mass charge is conserved,

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meaning it can't just disappear. It can move from one object to another,

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but, you can't spontaneously create a charge out of thin air.

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Now in our hydrogen atom here, we've got one negative particle and one positive

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one. Everything is nice and balanced, that's not always case. Some molecules

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have more protons than electrons. And well you know vice versa. It's pretty [two atoms working next to each other]

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common for electrons to only be loosely attached to the nucleus of an atom. They

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don't want to get tied down, so they're playing the field.

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Well these electrons can become completely free, just waiting for some

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new positively charged atom to come and sweep them off their feet. And it would

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have to be a positively charged atom, because like charges repel and opposite

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charges attract. It's like magnets, in fact it is magnets.[red magnet]

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Electricity and magnetism are closely related. So closely related in fact, that

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there's a whole field of study, within physics, called electromagnetism. Magnets

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have two poles, one positive and one negative, one north and one south. Maybe

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you've tried to push the positive poles of two magnets together and felt a

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strong resistance pushing your hands back. It's the whole like charges repel

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thing. And of course if you bring the positive side of a magnet, near the

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negative side of a different magnet, you're gonna have an instant attraction.[boy and girl holding magnets]

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All right you guys get a room. Any particle that has an electric charge,

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creates an electric field. An electric fields can be a little bit tricky

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because we can't see them. It's a lot easier to do physics with things you can

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actually look at. But electromagnetic fields are similar to gravitational

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fields. They do their work without requiring any movement from their source.

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If I want to make something move, I have to go over and make contact with it. So

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if a Girl Scout comes to my front door trying to sell me cookies, I have to make[girl scout at door]

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direct contact with the door to slam it in her face. Sorry, but, Thin Mints are

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addictive and I don't need to go down that road again. But an electromagnetic

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field, can push, or pull, something towards an object, without any contact at all.

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We're gonna prove this in just a minute. There's another way gravity and

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electricity are similar. They can both create potential energy. Gravitational

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potential energy is created when something is lifted off the ground. If I

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pick up a hammer, gravitational potential energy is stored, because the Earth's [man holding hammer]

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gravitational field is pulling on that hammer. You've learned that the hard way, if

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you've ever accidentally dropped a hammer on your toesies. Result? Potential

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energy, is converted into kinetic energy. It also results in the chemical

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energy in my body, being converted to sound energy, as I scream like a baby.

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With electricity, we have both electric potential and electric potential energy.

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Yep they're very similar sounding, but no, they're not the same thing.

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Electrical potential, is also called electrical potential difference. You can

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also call it voltage, which you've probably heard before. Electrical [chalkboard with facts]

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potential, is the potential energy that a theoretical charge would have, if placed

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in an existing field and it's what causes electricity, to go from point A, to

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point B, in a circuit. Electoral potential energy, is potential energy to charge

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your concern with, actually possesses. That might sound confusing, but

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electrical potential and electoral potential energy, will be the topic of a

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future video with equations and all sorts fun stuff. So, you know, don't sweat

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it for now. Nope, right now we're gonna go to the

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experiment with electricity. Normally I'd recommend leaving electricity to the

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professionals, like me. You shouldn't be messing around too much with electrical

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stuff. Because well, it doesn't always end well and no one likes the smell of [2 boys in school lab]

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burning hair. But in this case all we need is some tape, scotch tape, to be

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precise. Yeah there aren't gonna be bolts of electricity flying around, but this is

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still gonna be pretty cool. We need four strips of tape, each about five inches

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long. That's about 12 centimeters, if you don't speak, you know, American. Fold over

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a little bit at one end, so you've got a non sticky handle to work with. Okay now

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take two strips of tape. We'll get super creative and call them piece 1 and piece

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2. Stick them to your desk, or your table, or countertop, or whatever and pull [2 pieces of tape]

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each piece off of your chosen surface and keep them separated. Alright, job calls for

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two hands people. Okay now bring the non sticky sides, of each piece of tape,

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toward each other. The two pieces should repel each other just like that. Now

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bring one of the pieces near your hand, it should be attracted to you and of

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course it is. You're a total hottie right. But it's also due to electric charge.

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When you stick tape to your desk, it actually forms molecular bonds and when

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you pull the tape off those molecular bonds are broken and some electrons come

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along for the ride. Yeah, who know that, when you use scotch tape you're actually

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splitting up molecules. It's not quite the reaction you get from splitting atoms, and

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no that's a good thing. [nuclear bomb going off] Crafting should never go nuclear. All

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right well since there are extra electrons, sticking to the tape, well it

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now has a negative charge. And since we did the same thing with each piece, they

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both have the same kind of charge. Like charges repel, so they don't want

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anything to do with each other. But you and your hand? Well turns out your, a ray

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of positivity, in this cruel world, so the tape wants to snuggle up with you. [hand attracting tape]

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Because opposite charges attract. All right, now let's play with last two

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pieces of tape. Keeping with our awesome naming system, we'll call them

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3 and 4. Stick piece 3, to the non sticky side a piece 4. Before you pull them

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apart, you should know, that we're gonna be doing the same kind of thing. Holding

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the pieces close to each other and seeing what happens. All right any

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guesses? Will they repel each other, maybe attract each other, or maybe they'll just

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chill out and do nothing and this whole experiment will be a bust. Okay let's get

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to it. Pull piece three off piece four and hold

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them close to each other. Aw, now we've got attraction going on. In this case where [2 pieces of tape connecting]

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we had some hot tape, on tape action, piece three snagged some electrons from

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piece 4. Which means piece 3 is negatively charged and piece 4 is given

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off positive vibrations. Because well it lost electrons, giving it an imbalance of

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protons. When we've got opposite charges, we've got attraction. This experiments an

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example of static electricity. Static electricity is an imbalance of charges

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on the surface of an object. That imbalance can build and build, but [chalkboard with facts]

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eventually it will discharge. Alright we've dealt with static electricity

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before, ever grabbed a doorknob and felt a jolt? Well unless your parents have grounded

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you and wired your doorknob, so you can't leave. What you experienced was static

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electricity and static electricity is why you hear a wool sweater crackling on

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a dry winter day. We tend to think of static electricity as a small little zap,

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but it can get huge. In a thunderstorm there are a whole lot of little pieces[thunder cloud with ice]

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of ice moving around in the clouds, bumping into each other and swapping

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electrons. This creates an imbalance of charges and when you get a bunch of

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positively charged particles at the top of a cloud and negatively charged

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particles at the bottom, well then boom, lightning. Same basic thing happens

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between clouds and the ground. It's a huge [thunderstorm] amount of energy, but it's static

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electricity. Just like we created, with the tape experiment. And you can

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weaponize static electricity too. If you've got thick socks and carpet and

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you can shuffle your feet around and build up a static charge. Then find [socks on carpet]

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someone, who's been annoying you and reenact that scene from, Return of the

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Jedi. You know feel the force flow through your fingers and ouch yeah it's

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gonna hurt you too, but at least you're ready for it. That'll teach Bob to stop

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stealing your lunch. When you rub your feet on the carpet you're picking up

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electrons, giving yourself a negative charge. When you touch some filthy lunch

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thief, well those extra electrons go from you to him. [boy shocking other boy]

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It's kind of weird that there are these extra electrons all over the place. We

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tend to think of electrons, as part of atoms and they are. But there are lots of

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them, that are unattached and zooming all over the place and that's why

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electricity is able to move around. An imbalance of charges creates the

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attraction, that those negative electrons, just can't resist. And without

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electricity you wouldn't be able to watch this video or see your friends

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stupid snapchat videos. That she thinks are so funny, or you know, read about politics

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on Twitter. Well maybe this electricity thing isn't so great after all. [man looking at phone]

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