- [Narrator] We all love a good secret, and luckily, it turns out
the objects we use every day are absolutely full of them. From Coke's biggest secret
to how batteries really work, join me for yet another dive into some of the most amazing secrets hidden in everyday things. (light suspenseful music) - Whoa. (bell dings) - [Narrator] Cola can-do. If you thought that
Coca-Cola's best-kept secret was its elusive recipe, just wait till you see
what else they're hiding right under your nose. (funky upbeat music) Turns out there's far more to
a Coke can than meets the eye, a whole secret inner tube of plastic more. In the clip you just saw, the inner truth of an aluminum Coke can was revealed by a remarkable
chemical reaction. When submerged in a highly
corrosive alkaline solution containing sodium hydroxide,
like drain un-blocker, a coke can goes through a chemical process known as hydrolysis. This reaction causes the
aluminum in the can to dissolve, revealing a surprising
secret hidden within: A plastic lining, which
resists dissolving. But what's it doing there? Alongside carbonated
water and lots of sugar, soda contains acid. Coke is one of the most acidic
drinks in our refrigerators, namely because of its
contents of phosphoric and citric acid. These acids are corrosive in nature, giving Coke a pH reading of around 2.5, that's not much higher than battery acid. While we all know sodas like Coke can corrode our pearly
whites, thanks, Mom, did you also know that,
just like the alkaline we saw earlier, soda's acidity is strong enough
to eat away at metal, too? And seeing as Coke is
sold in aluminum cans, that's where our little tube
of plastic comes into play. Made from polymer or epoxy, this resin layer is installed
in the manufacturing process as a protective barrier
between the acidic soda and the aluminum walls of the can. Not only does this prevent the liquid from corroding the metal, in doing so, it also
protects the soda's flavor from being tainted by the dissolved metal. While you've probably never
seen a soda can in this form, manufacturers of canned drinks have been lining the insides of their cans with this plastic coating
for more than 50 years. But if manufacturers have
to go through the trouble of coating every can with
this protective layer, why not just do away with cans altogether in favor of purely using
glass or plastic bottles? Well, not only is aluminum the
most abundant metal on Earth, but aluminum cans also have a
much higher rate of recycling compared to plastic
and even glass bottles. So, the next time you crack one open, not only are you in for
some refreshing bubbles but also a true taste of
ingenious everyday design. Brush with the truth. After a reminder of just
what a can of Coke can do to our pearly whites, I'd say it's time for a good ol' brush. While we get up close and
personal with our toothbrushes at least twice a day, I hope, you might be surprised
at how little you know about what you're putting in your mouth. You've probably noticed
that most toothbrush heads have an array of different
colored bristles. While you might have assumed these are just an extra
touch for aesthetics, these bold bristles are hiding a very deliberate design
secret in plain sight. Often blue in color,
these colored bristles are known as toothbrush indicators, and tell us when it's
time to change brushes. On average, most Americans
change their toothbrush just twice per year, but according to the
American Dental Association, we should be switching out brushes at least four times a
year for good oral health. Toothbrush indicators are
designed to fade in color as you brush, and once most
of the color has disappeared, the bristles have worn down
beyond maximum effectiveness. That's when you know it's
time to change your brush, ya filthy animal. Cereal secrets. We're often told breakfast is the most important meal of the day, but it turns out there are also some seriously surprising
breakfast secrets served up right in front
of us every single morning. Nearly 3/4 of American households enjoy a bowl of cereal to start their day, but what most of those
households don't know is that there's a magnetic
secret hiding in every mouthful. Check this out. (funky upbeat music) If you thought mini cereal
boxes doubling as bowls, or coffee pods actually being half empty were breakfast's best-kept secrets, learning that cereal is actually magnetic probably just blew your
mind as much as it did mine. Many cereals are fortified
with a variety of vitamins and minerals as a way to help us meet our daily nutritional requirements. One of the most common extras found in your everyday cereal is iron. Unlike the iron that occurs
naturally in other foods, like beef and spinach, the iron in cereal is added as a fine
powder during production that look a lot like iron filings. Iron is ferromagnetic, which is the strongest type
of magnetism in existence, so even a small amount can
be attracted by a magnet. This is how this flake of
cereal is moving around, the iron inside it is
following the magnet. But before you swear off cereal forever out of fear of breaking your
teeth on chunks of metal, things aren't quite as
repelling as they may appear. Even if a serving of cereal contained a full dose of
recommended daily iron, which is eight milligrams
for men and 18 for women, both are even less mass
than a single grain of rice. So, there's really no danger attached to chomping down on your morning munchies, at least from the iron, all the sugar is another
story for another time. But who knew that eating
breakfast could be so metal? Battery-ception. I don't know about you, but
for most of my childhood, I assumed the batteries we use every day are full of liquid energy
that fuels our devices. However, most batteries of the
kind most household items use are actually dry-cell batteries
and don't contain liquid. Instead, they are made up
of electrochemical cells that convert stored chemical
energy into electrical charges. These cells are usually only capable of producing around 1 1/2
volts of electricity each, but if added together, they
can achieve a lot more. The 12-volt A23 battery, for example, often contains eight 1 1/2-volt cells hidden inside the larger battery wrapping. And the battery-ception
doesn't stop there. Some even bigger batteries, like this extra-long
life six-volt battery, are hiding their inner cells
within other batteries. Another unlikely place
you'll find instances of batteries in batteries
is in a Tesla car battery, which contains around 375 volts provided by hundreds of individual cells. While androids may
dream of electric sheep, turns out battery
manufacturers dream of how many different batteries they can
fit inside bigger batteries. Push for placebo. Picture this: You walk up to a crosswalk,
press the button, and wait for what seems like an eternity for that little walking
man to show himself. You cross the street and for
a split second, you wonder, "Did that button actually
do anything at all?" Well, you're not alone, and in reality, the
world is full of buttons that have been completely lying to you. Out of the 1,000 crosswalk buttons in New York City, for example, it's estimated that only about 100 of them actually serve any real function
to actively stop traffic. The remaining 900 are examples of what's known as a placebo button, a button that can be pushed
but has no effect whatsoever. But what's the point of all this? Invented in 1964, crosswalk
buttons were first introduced in a time when city
traffic was a lot lighter than the gridlocks we see today. At that time, traffic
lights would remain green until a pedestrian pushed the button. As the city became more
reliant on cars for transport and foot traffic increased, the crosswalk button began causing more problems than it was solving and was constantly stopping
traffic in its tracks. To solve this problem, city
planners have been gradually disconnecting buttons all over the city and replacing them with
timed traffic signals, and this has since been happening in other cities all
over the world, as well. So, why have the buttons there at all, if they don't do anything? While there's no official
answer to this question, some theorize that placebo
buttons are placed among us as psychological tricks that
give us an illusion of control. It's pretty frustrating regardless, especially considering
less-busy junctions, especially those in smaller towns, do still function as expected,
making it pretty hard to tell when you're being duped by a dud button. And like those found at crosswalks, push-to-close elevator
buttons are also suspected of employing the placebo button tactic. Turns out that the
push-to-close door buttons in most elevators have
been obsolete for decades, though the reason behind
it is pretty uplifting. When the US Americans
with Disabilities Act was passed in 1990, it meant
that elevator manufacturers had to remove the function of many push-to-close door button. This was to prevent people from getting in and closing the door
before a disabled person has time to get inside. However, while most of
these elevator buttons won't work by default for the public, many buildings have keys or codes that can render the buttons
operational in an emergency. While placebo buttons are
designed to be useless, I can think of three buttons
that are the complete opposite that you should push right now. If you're enjoying my latest
batch of everyday secrets why not head on down and
push those like, subscribe, and bell buttons to activate your lift off into a world of incredible facts and stories that are
sure to truly amaze you? All done? Great! Now, on with the video. Rated red. Even with the rise of streaming
and at-home entertainment, nothing quite matches up to a
trip to ye old movie theater. The soda fountains,
butter-drenched popcorn, and who can forget the
iconic movie theater seat? Now, you might have
noticed that more or less every classic movie
theater opts for red seats. This tradition partially stems back to a trend set by 18th-century
Italian opera houses, which were decked out with
regal-looking red seats to attract wealthy clientele. However, the color choice
in movie theaters today is also a very deliberate design decision that's specially selected
to trick your eyes. Our eyes have two different types of cells that work together to help us
detect the presence of light and color. The rods are most sensitive
to changes in light, shape, and movement but are not
good for color vision. The cones, meanwhile, are
most sensitive to color, but they work in bright light, which is why color is
harder to see in the dark. Different colors have
different wavelengths which affect our ability
to see them in low light. The shorter a color's wavelength, the easier it is for our cones to detect them in darker conditions. Red light has a longer wavelength than any other color in the spectrum, so it's the first color
we lose the ability to identify in the dark, even when other colors are still visible. This is known as the Purkinje effect, which is in full effect
when the lights go down at the start of a movie. As the red seats, walls, and curtains quickly
fade into the darkness, our eyes can focus their
full attention on the screen. And we're not done seeing red just yet. There's no doubt the image of
a red barn in a quaint field is as American as the Fourth
of July and apple pie. But have you ever stopped to
wonder why this iconic shade is a farmer's first choice? Some believe that farmers
painted barns in a rusty hue so they would appear to be made of bricks, a more expensive material that made farmers appear wealthier. Another popular belief is
that farmers paint barns red to help their cows find their way home, which seems smart until you find out that cows are colorblind in all colors except yellow and blue. Now, we could talk
about all these theories till the cows do, or don't, come home, but the reality is a much clearer picture. The early farmers that
settled in New England didn't have the extra money for paint, but still needed a way to
protect their unpainted barns from the elements. The result was a rusty-colored
mixture of skimmed milk, lime, linseed oil, and red iron oxide from the New England soil, which has been found
to limit the weathering of wooden surfaces. Talk about a humble beginning. Farmers, to this day,
still paint their barns red in homage to their forefathers' ingenuity, though utilizing the entirely
modern stroke of genius that is Home Depot. Bread tags. Without a doubt the most iconic
lunch menu item of all time, the humble sandwich would be nothing without two slices of good ol' bread. Americans eat more than
300 million sandwiches every single day, that's a human-to-sandwich
ratio of around one to one. That number of sandwiches requires a colossal amount of bread, so it's no surprise that a
loaf of bread is a staple for almost everyone's grocery list. You've likely noticed the colorful tags that seal bread bags, but did
you realize that these tags hold the secret to the
sandwich of your dreams? While the different colors are mostly there to help employees know when to refresh the bread on the shelves, being in on this color code
can also help you shop smarter. Each color tag corresponds to
a different day of the week, with each loaf tagged with a
color corresponding to the day the bread was baked. While there's no universal code for what each color symbolizes, generally the schedule
most grocery stores use is something like this: Loaves baked and packaged
on Monday are tagged blue, Tuesday loaves with green,
Thursday bread has a red tag, Friday with white, and
Saturday dons a yellow tag. If you're wondering why
there are no color tags for Wednesdays and Sundays, that's because these are
days that most bread bakeries take a day off from production. Now you know this tag secret, you can use your powers for
the good of all sandwiches by picking out the freshest
loaf every time you shop. Happy sandwiching! Speed chumps. While many drivers consider
them quite the nuisance, there's no denying that speed bumps are an essential part of road safety. Designed to slow drivers down in areas where there's a lot of pedestrians, speed bumps generally slow
drivers down to between two and 10 miles per hour. While driver and pedestrian
safety is the priority, some experts believe that speed bumps may not be so safe for our planet. According to the UK's
National Health Institute, because speed bumps cause
drivers to frequently accelerate and decelerate which
increases car emissions, they may be inadvertently
contributing to traffic noise and air pollution. As a solution, city
planners in London, England, have given fake speed bumps a test drive. How can a speed bump be fake, you may ask? Well, if you take a look
at these bumps side-on, you'll see that they're
actually completely flat and are merely an optical illusion. From the driver's seat point of view, the faux bumps are painted in such a way that they appear raised
like regular speed bumps, when, in reality, they are not. Experts claim the optical illusion could reduce emissions by up to 20% thanks to the smoother driving experience the faux bumps facilitate, as the drivers don't have to
accelerate as hard afterwards to counteract the decelerating
slope of a real speed bump. I mean, it's a pretty clever way to get people to drive safely
in an eco-friendly way, but does anyone else feel
like it's a little deceptive? Even the roads can't
be trusted these days. Let me know what you think
in the comments below. (cell phone keyboard clicking) Powerful symbols. While we all know we need food and water to power our bodies, there's one other power source that has become just as
essential in our daily lives, the coveted USB. Fully powered electronic devices have grown to rule our daily lives, and you probably pop your phone and other devices on to
charge multiple times a day without a second thought. While we all know that
this symbol refers to USBs, you might not know that this small but mighty emblem of power has
quite the mysterious history. Short for Universal Serial Bus, many intriguing theories
have been put forward over the years for what
the USB symbol means. The most popular theory
was that the symbol is a representation of Neptune's trident, known as the Dreizack. While the Dreizack symbolizes
the power of the sea, those who propose this theory suggest the USB's three-pronged trident could symbolize the power of
technology and adaptability. While it's fun to theorize,
the mystery of the USB symbol may have a more official solution. In 2020, Quora user Jim Dowse claimed that he was the designer behind the elusive USB symbol and that the real meaning behind it was a far cry from the suggested theories. Jim claims that he came up with the symbol while working as a technical illustrator at the Digital Equipment
Corporation in the 1980s, and it was later assigned to the USB, which was invented in the '90s. As opposed to any fantastical
links to mythology, Jim claims that the trident-like design is actually meant to
represent connectivity. The larger circle at
the base of the symbol represents a computer,
while the smaller circle and triangle and square connected to it represent the multiple different outputs a device like USB could
potentially be used for. So, when the USB technology emerged, the generic symbol Jim had
been tasked with designing proved perfect for it. Of course, these are merely
the claims of one man online, so could be fabricated, but
they certainly seem believable. And it's not just the USB, there are a mass of technological symbols whose true meaning escapes
our notice every single day. Take the power symbol, for instance. The simple circle broken by a small line is believed to have been
derived from the binary system, with the number one standing for power and zero indicating power off. But, hey, don't hit that
power button just yet, we've got even more amazing
secrets coming right up. Heinz and seek. One of the most recognizable
brands out there, there's no doubt that Heinz is the undisputed king of condiments. When you go to a restaurant
that's serving Heinz, you know that means
they care about quality. Or does it? As an established household brand, Heinz costs more than many ketchups used in the catering industry, but some restaurants
have been using this fact to fool their customers. Shockingly, 20% of
restaurants surveyed by Heinz admit to refilling Heinz ketchup bottles with cheaper alternatives to save money, and Heinz isn't happy. In response to this epidemic
of counterfeit ketchup, Heinz has devised a solution,
and it all lies in the label. On some of the bottles
distributed to restaurants, Heinz has transformed their
iconic label into a control tool to help consumers check whether the ketchup they're
being served is truly Heinz. The new label includes a red outline that has been perfectly
color-matched to Heinz ketchup. On an authentic bottle of Heinz ketchup, this border is almost invisible, but if there's imposter sauce inside, it stands out as a blaring warning that you're the victim of ketchup fraud. That'll teach those saucy devils. Cases cracked. While it's a no-brainer that
a suitcase needs a zipper, you might have noticed that most suitcases have not just one but two little
pull tabs on their zippers. Those nifty little sliders are known in the industry
as cars, by the way, so there's a free hot steaming
fact right out of the gates. Now, we're all familiar with the anxiety that comes along with traveling
with an overloaded suitcase, and while it might seem
like the bulging case is working against you, its two zippers are secretly
rooting for you to succeed. While an overloaded case could pull a single zipper car apart, a second zipper pull acts as a failsafe if the first were to fail, allowing you to still close your case. Not only that but having two zipper pulls allows you to reach into just
a small corner of your case without having to open the entire thing. Two zips also allow you
to padlock your suitcase for extra security even
without a built-in lock system. Yet another lesser-known protective design
feature on some suitcases are these plastic tabs that
help to protect the case from the bumpy journey that happens behind the scenes at airports, offering a little shock
absorption in case your case meets with a disgruntled baggage handler. Because, Lord knows,
careless baggage handlers certainly exit. "Dang it, Bobby, my prized glass egg "and porcelain doll
collection was in there." Match point. Whether you're a tennis player or not, everyone is familiar with
the iconic tennis racket, but I'll bet you didn't
realize just how much thought is put into its design. This open space just
beneath the racket's frame is called the throat, and while you've probably
seen players use this area to hold spare balls, that's
not really why it's there. Also known simply as the triangle, the throat is an integral part of a tennis racket's aerodynamic ability. The open space allows air to pass directly through the racket, creating a lot less drag when swinging. It's something absent from
vintage tennis equipment and makes the old wooden
rackets feel pretty cumbersome by comparison. For a second serve of tennis factoids now, while everyone knows that
the markings on the court play an integral role
in every tennis match, you might not realize that the
position of the court itself can be even more important. While you'd never notice
it from the ground, if you take a look from the sky, you'll find that most tennis courts, like these ones at Wimbledon, mysteriously face the
exact same direction. But what's the reason for
this aligned orientation? Seeing as tennis is
mostly played outdoors, the position of the sun
can play a significant role in the fairness of a game. If the sun rises or sets
right behind a player, it could really impact
their opponent's vision and performance. Seeing as the sun moves from
east to west during the day, many tennis courts are specifically built to have a north-south orientation to avoid the sun as much as possible. This way, the sun will always be located to the side of the court, with any glare affecting
both players equally. Unfortunately, many clubs
are built on plots of land that don't offer enough space for a real choice of orientation. So, if you ever find
yourself losing a match, double-check which way
your court's facing, it might be that you're
at an unfair disadvantage. Or at least, you can
choose to blame it on that. Conical cleverness. The office water cooler is
the best place to get in on all the office gossip. But what you may not realize is that there's an even
juicier everyday secret right there in your hand. While easy to hold, the cone-shaped cups commonly found by water coolers
are specifically designed to encourage quick drinking as the cups can't be
placed on flat surfaces. This also prevents employees
from taking water-filled cups back to set down on desks,
where it could be knocked over and spilled over computers and
other electrical equipment. But, the true reason
behind the cone cup's shape may really lie with
sustainability and money-saving. As water cooler cups are
designed to be single-use, cone-shaped cups are
actually less wasteful, as they require less paper to construct compared to regular shaped
cups, and hence cost less too. Plus, most importantly of all, they make for one hell of a stylish hat. Shave new world. For many guys out there, shaving is an essential daily ritual, but the next time you lather up, you'll know there's a
hidden everyday secret that's been smoothly passing you by. Check it out. While you might be wondering why there's a blank Capri Sun inside your can of shaving gel, I wouldn't recommend trying a swig. While shaving foam is packaged
in a traditional aerosol can containing both product
and gas mixed together, shaving gel uses what's known
as bag-on-valve filling. In cans with these
latter types of fillings, the product is filled
into an aluminum pouch which is attached to the valve. The extra space in the can is
filled with compressed air, which squeezes the pouch every
time you press the trigger at the top of the can. Bet you never thought there
could be so many mechanics behind a smooth chin. It's a shave new world, indeed. Ballin' in secrets. With hundreds of domestic
leagues, cup competitions, and international tournaments
taking place each year, countless games of professional soccer, or football, for most of the world, are being played every single day. If you're one of the 3 1/2
billion footie fans worldwide, you've probably lost count of the number of games you've watched. But you'll never watch
one the same way again after hearing this. Thanks to the power of technology,
the role of the referee has become more precise than ever before, with the introduction of video
assistant referee systems back in 2012. But now, a new footie invention has booted its way onto the field, and it could change the face
of soccer as we know it. In 2022, the World Cup introduced these rechargeable footballs that are specially
designed to help referees make decisions during games. The balls are fitted with
special electronic sensors suspended inside. The sensors are able to send
data 50 times per second to the VAR system to help determine the ball's
precise position and kick point which helps detect offside
disputes more accurately for a fairer game overall. Is it a little ridiculous that
professional soccer players now need to charge their
balls before playing? Maybe, but honestly, with
the way the world's headed, it's probably not long before we all have to plug ourselves into
the wall to charge overnight, so perhaps we should just
get used to it. (chuckles) What do you make of our latest
batch of everyday secrets? Do you know of any we've
missed so far in the series? Let me know in the comments below, and we'll be sure to use the
best ones in our next part. Thanks for watching. (gentle thoughtful music)
