Bread Toaster
0:00:05 Grids hold the bread in place
0:00:07 Heating plates toast the bread
0:00:10 There is a drawer for crumb collection
0:00:12 a magnet
0:00:14 an integrated circuit
0:00:16 and a potentiometer
0:00:18 pushing down the lever, slides the bread downwards
0:00:21 the spring holding the bread up is now stretched.
0:00:25 why aren't the slices come flying out of the toaster when we release the lever?
0:00:30 electricity is on the job
0:00:32 there is a small V shape plastic piece on the lever
0:00:35 as it moves down, it splits apart the two metal strips of the electrical switch
0:00:40 the two electric terminals make contact
0:00:43 current races through and the toaster begins its impressive work.
0:00:47
0:00:49 the spring may be poised to fling the bread across the counter
0:00:52 but the current activates an electromagnet at the bottom of the toaster.
0:00:57 There is a metal plate hidden under the lever
0:01:00 the magnet attracts metal plate and nobody moves.
0:01:04 as long as there's current, the bread's not going anywhere.
0:01:07 Smart stuff
0:01:09
0:01:10 Now, for the toasting, again, electricity's in charge.
0:01:14 The electricity shoots through a metallic wire,
0:01:17 but the wire offers a lot of resistance
0:01:20 and that resistance is the reason the wire heats up.
0:01:25 not only does it heat up, but it heats up really, really fast.
0:01:29 the temperature of the wire blasts in between 1100 and 1200 degrees Fahrenheit
0:01:34 no joke, 50° more and we could smelt aluminum
0:01:38
0:01:39 This wire is also amazing, it's an alloy of nickel and chrome that can withstand volcanic lava
0:01:45
0:01:46 instantaneously, heat reaches the bread which starts to warm up.
0:01:51 At this point very complex chemical reactions begin in the bread and the slices start to darken
0:01:57 also very rapidly
0:02:00 The glucose carbonyl group reacts with the amino acid of the amino group to produce N-substitute
glycosylamines
0:02:06
0:02:07 Oke, doke, no need to remember any of that.
0:02:10 What counts is the bread's toasting, but its situation's critical.
0:02:14 Why?
0:02:15 in order to cook the perfect size of toast, the heat must not attack the center of the slice;
0:02:20 if that happens; the humidity trapped in the center of the bread would evaporate
0:02:24 leaving you with horror of horrors: dry toast
0:02:27 the trick is to super heat the slices, intensely but quickly
0:02:31 the nickel-chrome wire is perfectly suited, because it reacts in a blink of an eye
0:02:37 Things can still get dicey, heating the slices that quickly and intensely can lead to carbonization
0:02:43 which is why it's key to pop them at just the right moment.
0:02:46 Whose job is that? Electricity again.
0:02:49 the toast will pop at the exact moment the cooking time said by the user is off
0:02:54 Cooking time is set by a turn of the browning control diode
0:02:57 which is simply a turn of the toaster's potentiometer.
1
0:00:20 The compact fluorescent bulb
0:00:22 it creates light
0:00:24 but in a very unique way
0:00:26 it uses electricity to excite gases present in the bulb
0:00:30 to create a chain reaction
0:00:32 until it finally emits visible light.
0:00:35 First it produces ultraviolet light which can't be seen
0:00:40 Then it uses that invisible light to create fluorescent light which we can see
0:00:45 That's right, it creates light twice
.
0:00:50 The compact fluorescent bulb:
0:00:52 it uses electricity to create uninvisible light and recycles it to create a visible light
0:00:58 it really is an energy recycler
0:01:02 ok, but how does it work?
0:01:05
0:01:07 the compact fluorescent bulb
0:01:09 electrodes
0:01:10 tube
0:01:11 inside a fluorescent coding
0:01:14 and a tiny drop of mercury
0:01:16 and a mix of rare gases.
0:01:18
0:01:20 for that bulb to shine a light, three things have to happen:
0:01:23 One, electricity must flow through the gases in the bulb
0:01:27 Two, that electricity must excite the mercury so that it creates invisible light
0:01:34 and three, that light must excite the fluorescent tubes coding
0:01:38 and make it light up.
0:01:39
0:01:41 to find out how all this excitement creates visible light
0:01:44 we've got to bust open that bulb
0:01:47
0:02:20 First thing to know, the environment in that bulb is very special
0:02:25 it's all about pressure
0:02:27 or, rather, the lack of pressure
0:02:30 the gas pressure
in the bulb is hundreds of time lower than normal atmosphere
0:02:36 that's key
0:02:38 At such low pressure, mercury becomes a gas
0:02:41
0:02:42 and that's important, because that mercury vapor floats floats
0:02:45 and mixes with the other gases in that tube.
0:02:48
0:02:50 when the light bulbs is turned on, electricity flows to the bulb through the electrodes
0:02:55 setting off a chain reaction
0:02:57
0:02:58 to create light, electricity must travel through the tube
0:03:02 but the mix of gases inside that tube is not conductive
0:03:07 electric current can't flow through this mix
0:03:10
0:03:11 electricity must transform the mix of gases inside the tube by energizing the mix.
0:03:17 Once it's energized, the mix of gases changes state,
0:03:21 it's now highly conductive,
0:03:24 an electric current can flow through it;
0:03:27
2
0:03:29 this is when the mercury vapor becomes essential
0:03:32 when an electric current excites mercury,
0:03:36 it reacts by emitting ultraviolet light: invisible light
0:03:40 Now that bulb has created light once, it can't be seen,
0:03:45 but it's got a lot of energy.
0:03:48 That's a good thing, because the bulbs are great energy
0:03:53 when that invisible but high energy light reaches the fluorescing coding,
0:03:57 on the inside of the tube
0:03:59 that energy is not lost
0:04:01 because it then, excites the fluorescing coding
0:04:04 the coding absorbs all the energy from the ultraviolet light
0:04:08
0:04:09 when fluorescent matter is excited by an invisible but highly energetic light,
0:04:14 it reacts, it emits light
0:04:18 Light that has less energy than the ultraviolet radiance that provoked it
0:04:22 but light is visible.
0:04:24
0:04:26 Inside that bulb, light's been created twice.
0:04:30 Awesome
0:04:30
0:04:33 The compact fluorescent bulb, it's an incredible invention
0:04:37 it uses electricity to transform a mix of gases and make it conductive
0:04:43 then, it uses the electric current to excite mercury
0:04:46 which emits invisible light
0:04:48 which excites the fluorescent coding
0:04:50 which emits visible light
0:04:53 hi o
0:04:54 that bulb takes an invisible light and recycles it to create a visible light
0:04:59 It really is an energy recycler.
3
The digital camera
0:00:16 It’s all about light.
0:00:19 The digital camera
0:00:21 It's revolutionized photography by transforming light into electricity
0:00:27 Everything is there to draw in light
0:00:29 from the camera’s buttons, controls and dials down to the lenses
0:00:35
0:00:38 What the digital camera does replay is what makes it so revolutionary
0:00:43
0:00:45 It turns light into electrical charges that become the image captured on the screen.
0:00:50 Light particles or photons leave the source
0:00:53 Bounce off the subject and enter the camera through a series of lenses.
0:01:01 the photons, then, follow a designated path
0:01:03 on the way from photon to photo
0:01:07 a series of lenses allows the photographer to capture the clearest image possible
0:01:13 this lens diaphragm is what controls the amount of light that the photographer allows in
0:01:18 through the camera's opening or aperture
0:01:22 After crossing the diaphragm, the lenses and entering the aperture,
0:01:27 the light bounces off a mirror and heads for the viewfinder.
0:01:31 before it gets there, the light is flipped over as it passes through a prism
0:01:37 that's so the image seen in a viewfinder is right side up.
0:01:41 If the photographer likes the image,
0:01:44 time to press the shutter button
0:01:47 The mirror lifts and the light rushes in.
0:01:50 For a fraction of a second the light is not heading in the direction of the viewfinder,
0:01:55 but for the very heart of the digital camera, the image sensor.
0:02:00 the duration of this fraction of a second depends on the shutter
0:02:04 that opens just long enough to expose the sensor to light
0:02:08 Now, to the real heart to this digital revolution.
0:02:11 the elements that captures the image
0:02:13 the image sensor a tightly structured grid
0:02:17 made up of extremely tiny light sensors.
0:02:19 When the photons hit the light sensor
0:02:22 they're absorbed by the semi conductive material it's made of.
0:02:25 For each photon absorbed the light sensor emits an electrical particle called an electron
0:02:31
0:02:32 the photons’ energy transfers to the electron, that's the electrical charge
0:02:38 the brighter the image the stronger the electrical charges.
0:02:41 so, each electrical charge has a different intensity.
0:02:45 A circuit board then converts the different intensities into computer language.
0:02:49 They represent millions of tiny colored dots that make up a photo:
0:02:54 the pixels
0:02:56
0:02:58 the more pixels in the picture the better resolution. It's all about light. The digital camera
4
The Electric Bike
0:00:01 The electric bike
0:00:04 The crankset
0:00:06 The chain
0:00:08 The motor
0:00:10 The wheel powered by the motor
0:00:12 and the famous freewheel mechanism
0:00:15 the electric mechanism is made of a fixed stator:
0:00:19 it's the axel around which the wheel turns
0:00:22 and the roller to which the wheel is attached
0:00:25 A battery supplies electricity to the motor
0:00:28 Three lead acid cells supply 36 volts
0:00:31 Howell's commune electric bikes travel 30 miles and they speed 15 miles/hour without pedaling once
0:00:38 To understand more, a little more destruction
0:00:42
0:01:21 The stator of the motor is attached to the frame of the electric bike.
0:01:26 It's fixed, it doesn't rotate.
0:01:28 The motor loader is the piece that moves,
0:01:31 it turns around the stator and is attached to the rear wheel of the e.b.
0:01:36 When the rotor turns, the wheel also turns.
0:01:41 Attached to the rotor is the first half of the freewheel mechanism
0:01:45 The second half is in the inside of the sprockets.
0:01:48 When the crankset turns, the chain moves the sprockets.
0:01:52 The notches at the center of the sprockets push on the pawls 0:01:56 two little mobile pieces of metal on each side of the first half of the freewheel mechanism
0:02:02 Since the notches push on the pawls,
0:02:05 the movement of this sprocket is transmitted to the rotor
0:02:09 and the wheel turns.
0:02:11 If the motor is operating at full power and the cycle slows down or starts pedaling low together
0:02:16 the chain no more moves the sprockets
0:02:19 They can do a stand steel
0:02:21 The rotor turns at full speed
0:02:24 Since the pawls are mobile, they slide across the notches
0:02:28 So the rotating movement of the rotor is not transmitted to the sprockets which remain motionless
0:02:34 The chain doesn't move
0:02:35 And the crankset is completely separated from the rotor movement
0:02:39 Thanks to the freewheel mechanism
5
Hot Water Heater
0:00:01 Hot water heater is an excellent conductor of heat
0:00:03 it only needs forty minutes to heat 40 gallons of cold water.
0:00:08 but the hot water heater is also a terrible conductor of heat
0:00:12 it retains heat in its hot water rather than transfer to the outside air.
0:00:19 Thanks to its split personality, the hot water heater is a master of oneway heat transfer.
0:00:25 From the flame to the water, heat flows
0:00:28 From the water to outside air, heat does not flow.
0:00:32 hein, but how does it work?
0:00:34
0:00:38 The heat source in this gas water heater is the burner flame
0:00:43 a chimney extends from the bottom to the top of the reservoir
0:00:46 to efficiently transfer heat
0:00:49
0:00:50 cold water comes in through the top
0:00:52 sends to a pipe, absorbs heat and leaves through the exit pipe.
0:00:57
0:00:59 Now, how couldn't hot water heater be a conductor when it's time to heat the water
0:01:03 and an insulator when it's time to keep heating
0:01:06
0:01:08 In order to understand its split personality, we have no choice:
0:01:12 Time to open her up
0:01:14
0:01:41 The bottom of the water heater and the chimney are both made of metal
0:01:45
0:01:47 That's not for nothing
0:01:49 Metals do a fantastic job of conducting heat from one place to another
0:01:52
0:01:54 That's because speaking on an atomic scale, they're free electrons.
0:01:59 Tiny particles that move from atom to atom spreading heat
0:02:03
0:02:05 OK, the flame heats the air which heats the bottom of the water heater
0:02:10 and entrance the chimney
0:02:12 Thanks to the conductive properties of metal, the heat is transferred to the
.
0:02:16
0:02:18 but there is more, a baffle in the chimney slows the air
0:02:23 it must work its way through the zigzags
0:02:26 which allows more time to transfer more heat to the water
0:02:29 a clever design which optimizes heat conduction
0:02:32
0:02:36 but if conduction is so great at transferring heat from the burner to water
0:02:40 then it can also conduct the heat from the hot water to air outside the tank
0:02:45
0:02:46 to prevent that, the water heater's also a perfect insulator
0:02:49 thanks to this polyurethane foam
0:02:52
0:02:55 it's exact opposite of metal,
0:02:57 instead of transferring heat, it traps it, how?
0:03:01
0:03:02 The foam is made up of billions of tiny gas bubbles imprisoned in plastic
0:03:07
0:03:08 Gas bubbles are terrible at conducting heat
0:03:13 and gas molecules are extremely spread out.
6
0:03:16 This makes transferring heat from one to the other much more difficult than in a solid.
0:03:22
0:03:23 Also, the plastic surrounding each bubble is, itself a bad heat conductor
0:03:28 it doesn’t have any of those famous free electrons
0:03:32 The heat is trapped and stays inside the reservoir
0:03:36 thanks to insulation the water heater keeps water hot a long time
0:03:42
0:03:44 the water heater really does have a split personality:
0:03:47 there's no possible doubt, it's an excellent conductor
0:03:51 transferring maximum heat from the burner to water in the
0:03:56 but it's also a champion of insulation
0:03:58 when it comes time to keep heat inside
7
The Lawnmower
0:00:05 A generator of hurricanes?
0:00:07 at first sight it only looks like
0:00:09 a generator of a really tiresome household chore
0:00:12
0:00:13 at least it moves forward on its own
0:00:15 thanks to the energy of the motor
0:00:17 as soon as we yank the cord it begins turning
0:00:20 but it turns far too quickly to transmit the same movement directly to the wheels
0:00:25 if it did, the motor would instantly start racing across the lawn at 75 mph
0:00:29
0:00:30 the challenge?
0:00:31 taming the motor's incredible power
0:00:34
0:00:47 To start, the movement of the motor is transmitted to a pulley
0:00:50 which turns at the same speed
0:00:52 then we slow it four ways
0:00:54 First, the pulley transmits its movement to a much larger pulley
0:00:58 It takes several turns of the smaller pulley to turn the larger second one
0:01:03 The machine's already a little calmer
0:01:05 Second, the transmission belt making the two pulleys isn't doing a perfect job
0:01:11 It actually sleeps and slides on the pulleys intentionally
0:01:15 It's yet another way to calm the beast
0:01:18 Third, the second pulley transmits its movement to a gear of an even larger diameter
0:01:23
0:01:24 the rod at the end turns even more slowly than the pulleys
0:01:28 Forth, the wheel makes one turn for every four turns of the rod
0:01:33 Thanks to this ingenious set up, lawn mowing has managed to avoid becoming an extreme sport
0:01:39 Together: the pulleys, transmission belt and gears manage to restrain the power of the motor enough
0:01:45 to make the wheels turn 20 times slower
0:01:48 but, wouldn't it have been simpler to make a
in the first place?
0:01:53 no way, to model one, we need hurricanes.
0:01:57 Creating hurricanes requires a motor capable of turning the blade extremely fast
0:02:02 To see the rotation of the blade moves air
0:02:04 is this serious under steam
0:02:06 and all that air isn't just moving randomly
0:02:10 the blade is curved at its extremities and near the centre
0:02:13 when the blade turns these curves generate whirl winds of air
0:02:17 whirl winds that spin at more than 75 mph
0:02:21 hurricane winds speeds
0:02:23 the many hurricanes straighten the grass blades
0:02:26 which is key for a perfect cut
0:02:28 a fraction of a second later the blade whips around
0:02:31 and chops them at 225 mph, record speed in F1
0:02:37 cleverly calculated.
0:02:38 Oh but, there's more
0:02:40 to get the cut grass blades to their final destination
0:02:43 the lawnmower relies on laws of fluid dynamics
0:02:48 if the
open a
is created,
0:02:50 the air pours into the area where pressure is the lower.
0:02:54 The cut grass is pulled along and then pushed outside.
8
The Tattoo Machine
0:00:18 The tattoo machine
0:00:20 the needle, this is what goes up piercing the skin
0:00:24 the footswitch which starts and stops the tattoo machine
0:00:28 and the variable voltage power supply unit
0:00:31 which controls the force with which the needle pierces the skin
0:00:34 when the foot switch is pressed down
0:00:36
0:00:38 it's obvious that makes the tattoo machine work
0:00:41 but to understand how, nothing beats taking it apart
0:00:45
0:01:07 Let it all out,
0:01:08 and it's obvious to see
0:01:10 the tattoo machine is an electric circuit
0:01:13 current comes through the positive terminal
0:01:17 passes through two coils made of copper wire
0:01:23 and then a contact screw
0:01:27 it continues across two metal strips
0:01:32 and exits through the negative terminal.
0:01:34 pretty simple!
0:01:35
0:01:37 to move the needle,
0:01:38 the tattoo machine relies on electromagnetic force.
0:01:42 when electric current passes through a copper coil, it's magnetized
0:01:47 it becomes an electromagnet
0:01:49 that's exactly what happens to the two coils in a tattoo machine
0:01:54 Right above the two coils is the armature bar
0:01:57 a piece of metal with a rod attached to it.
0:02:00 At the end of the rod is the needle
0:02:03 When electricity transforms the two coils into electromagnets
0:02:08 they attract the armature bar, thanks to electromagnetism
0:02:10
0:02:12 The force of attraction is powerful enough to bend the normally rigid metal strip
0:02:17 to which the armature bar's attached.
0:02:19 the result :
0:02:20 the armature bar moves downward
0:02:22 and sticks to the coils
0:02:24 bringing the rod with it
0:02:25 along with the needle at its tip
0:02:27 and a hole is pierced in the skin
0:02:29 As devices go, the tattoo machine is both
0:02:33 simple and elegant
0:02:35 simple because it's a basic
0:02:37 that's closed and opened over and over again
0:02:39
0:02:41 elegant
0:02:43 because it's the tattoo machine itself
0:02:45 that cuts and re-establishes the circuit
0:02:47 All that to move a needle
0:02:49 that pokes skin
0:02:53 A master piece
9
The Coin Changer
0:00:01 It is made of a circuit board and three compartments
0:00:05 one where the coins are identified
0:00:07 a second where they are sorted
0:00:09 and a third where the coins are stored
0:00:12 To understand how the coin changer does all this we have to take it apart.
0:00:18
0:00:40 Inside the coin changer’s first compartment is a set of copper coils diodes that emit light and sensors
0:00:48 Inside the second compartment is a coin sorting system
0:00:52 When the coin goes into the vending machine slot it drops down the shoe
0:00:56 into the coin changer onto a narrow ramp.
0:01:00 From there, the coin rolls into the first compartment
0:01:04 as it rolls, it passes between two coils of copper wire. These coils have an electric current running
through them
0:01:12 when electricity circulates in a copper coil, that coil becomes an electromagnet
0:01:18 Like all magnets, an electromagnet generates a magnetic field.
0:01:23 So, when a coin rolls between the coils, it’s moving into a magnetic field.
0:01:29 As it rolls through, the coin disturbs the magnetic field.
0:01:33 It's the way it disturbs this field, that’s key,
0:01:37 because different metals disturb the magnetic field in different ways.
0:01:41 And a larger coin disturbs the field more than a smaller one
0:01:46 When the magnetic field is disturbed it alters the electric current that’s running through the coils.
0:01:53 By registering the changes in the electric current in the coils,
0:01:57 the coin changer's circuit board can begin to identify the coin.
0:02:02 Now the coin changer knows two things about the coin
0:02:06 The kind of metal it’s made of
0:02:08 and the amount of metal that’s in that coin.
0:02:10 Thanks to the electromagnets.
0:02:14 To complete I.D.ing the coin's denomination the coin changer has to know the coin’s size.
0:02:20 To do this, it uses light.
0:02:23 As the coin continues to roll, it passes by a diode that emits a ray of light
0:02:29 and a sensor that receives the ray of light.
0:02:31 It then passes by a second diode and it’s sensored.
0:02:36 Each time the coin passes a diode it blocks the ray of light .
0:02:41 The circuit board measures how long the coin blocks each of the two rays of light it passes
0:02:46 A quarter will block the ray’s blade longer than a dime will,
0:02:52 That’s how the circuit board determines the coin’s size
0:02:57 Now that the coin changer knows for certain what kind of coin it has got, it can sort it.
0:03:03 That happens inside the coin changer's second compartment.
0:03:08 Retracting gates guide the coins into their respective
.
0:03:13 The coins are now all sorted by denomination.
0:03:17 Now the coin changer knows exactly how much money has been inserted
0:03:21 and passes it all alone
0:03:23 by electronic signals to the vending machine main circuit board.
0:03:28 Mission accomplished
10
The speakers
0:00:02 The Speakers
0:00:04 All the functioning of this basic looking box depends on the interaction
0:00:08 between electric current, a copper coil and a simple plastic membrane
0:00:13 The current and coil cause the membrane to vibrate
0:00:17 the membrane pushes and pulls the surrounding air
0:00:20 Essentially it pounds waves into the air, sound waves
0:00:24 By controlling the electric current that moves this small plastic lining
0:00:28 the speakers can make any sounds imaginable
0:00:31 Let's look how it works:
0:00:34
0:00:51 In the enclosure, are two speakers
0:00:53 one for low sounds and one for highs’
0:00:57 Both have the exact same parts and work the exact same way
0:01:01 a permanent magnet
0:01:02 a diaphragm, just a plastic memory
0:01:06 stuck to the membrane a copper coil;
0:01:09 the coil's inserted into the magnet
0:01:11
0:01:13 when the current circulates through the copper coil,
0:01:16 it creates an electromagnetic force that pushes on the coil
0:01:21 by changing the direction of the electric current in the coil,
0:01:25 we change the direction of that force
0:01:28 so, the coil is pushed one way when the electric current circulates one direction
0:01:33 and the opposite way, when the current changes direction
0:01:37 since the coil's attached to the diaphragm,
0:01:40 where one goes, the other goes too.
0:01:43 this interaction is the key to understanding how a speaker works
0:01:47 All of this happens in a fraction of a second
0:01:50 because the current changes direction very quickly
0:01:54 up to 26'000 back and forth times a second
0:01:57
0:01:58 How often a direction the current changes depends on the sounds the speaker is required to make.
0:02:04 low notes will get the current to move back and forth about 40 times in one second
0:02:09 that means, the diaphragm will vibrate 40 times in one second
0:02:13
0:02:14 the faster the current changes direction, the faster the diaphragm vibrates
0:02:18 and the higher the sound coming out of the speaker
0:02:21
0:02:22 a small electric circuit in the speaker enclosure directs traffic
0:02:26 sending the proper electrical signals to the proper speaker
0:02:29 low sounds go to the bigger low frequency speaker
0:02:32 while high sounds go to the high frequency speaker
0:02:36 so, it's by controlling the speed of the changes in direction of the current
0:02:40 that we control how low or high the sound coming out will be.
0:02:45 Simple, efficient and cool
0:02:48
11
The Electric Guitar
0:00:02 The Electric Guitar
0:00:03 Clearly a musical instrument
0:00:06 but why electric?
0:00:08 because it transforms the vibrations of the strings into electric current
0:00:12 and it's this current that's sent to an amplifier
0:00:14 in fact, to produce music the electric guitar makes electricity
0:00:19 ok, so how does it work?
0:00:21
0:00:24 Here is the most important part of an electric guitar
0:00:27 the pickups
0:00:29 they are the ones that transform the strings vibrations into electricity
0:00:32 so they can be sent to an amplifier for everyone to hear;
0:00:36 but to really get it how about a little destruction?
0:00:39
0:00:47 while the body of the guitar clearly contributes to the look of the instrument
0:00:51 it does not contribute a whole lot to the sound
0:00:54 that's because it's solid
0:00:56 unlike an acoustic guitar which is hollow
0:00:59 the neck of the electric guitar is fixed to its solid body with four screws
0:01:03 along the neck are the frets
0:01:05 and at the far end the head where the strings are wrapped around the tuning pegs.
0:01:10 the strings are metal for a reason
0:01:13 their magnetic properties interact with the pickups
0:01:16 and it’s this magnetic interaction that creates the electric current
0:01:20 that will be amplified to unleash the sound of the instrument
0:01:23 at the body end of the strings the bridge and a metal lever
0:01:27 attached to the bridge are three springs setted into the back of the guitar
0:01:32 the metal lever, known as the whammy bar loosens or tightens the strings to create a tremolo effect.
0:01:38
0:01:40 cool, even if that's nothing compared to the amazing performance of the pickups,
0:01:45 turning mechanical vibrations into electricity
0:01:49 the pickups are basically six magnets wrapped with a very fine copper wire coil
0:01:56 the wire is thinner than a human hair
0:01:59 and wound around the magnets 7200 times
0:02:02
0:02:03 uncoiled, it would stretch the length of 8 football fields
0:02:07
0:02:08 these knobs control volume and tone
0:02:12
0:02:13 this is the pickup's selector switch
0:02:16 the ton knob accesses a kind of filter
0:02:19
0:02:21 it works for the capacitor built into this
0:02:24 it gets rid of high frequencies, keeping the guitar a warmer, fuller sound
0:02:28
0:02:32 but tone and volume mean nothing if you can't hear a thing
0:02:36
0:02:38 the pickups are key, they really pick up the strings' vibes so that they can be amplified.
0:02:44
0:02:45 all this using only a few magnets and a coil.
0:02:48
0:02:49 the pickups' magnets produce a stable magnetic field
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0:02:53 that is until the guitar's strung and the vibrating metal strings disturb the magnetic field
0:02:59 inducing an electric current in the coil
0:03:02 the current fluctuates in keeping with the movement of the metal strings
0:03:07
0:03:09 so, if you plugged the A string, it vibrates at 440 cycles a second or 440 hertz
0:03:16 and that will induce an electric current of the same frequency in the pickup.
0:03:21
0:03:23 what's the point of a pickup's selector switch?
0:03:26
0:03:27 well to get a particular sound
0:03:29 guitars can choose one or combo pickups
0:03:32
0:03:34 the pickup closest to the bridge, where string tension is high, picks up high frequency sounds.
0:03:41 the pickup closer to the neck, where the tension is less, registers more bass
0:03:45
0:03:47 but the electric guitar is nothing without an amplifier
0:03:51
0:03:52 in fact the amplifier's considered part of the instrument
0:03:55
0:03:56 unplugged the 2-volt current from the strings vibes won't get power chores to the back of the stadium
0:04:03 it needs a boost first by a pre amp
0:04:06 and then by the amp itself
0:04:08
0:04:09 and the louder, the more distortion
0:04:12 Guitar amps are built to enhance distortion
0:04:16 the incoming electric current totally overpowers the circuitry and brings out the buzz
0:04:20
0:04:23 it can be so loud, it can actually cause the strings on a guitar to vibrate
0:04:27 setting of scritching feed back
0:04:30
0:04:31 Now, that's a buzz
0:04:33
0:04:34 Surprisingly, to produce music, the electric guitar makes electricity
0:04:38 Thanks to the laws of electromagnetism
0:04:41
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