Bill Nye The Science Guy - S03E02 - Pressure - Best Quality

Summary

The script is a lively educational presentation about pressure, featuring experiments and demonstrations to explain the concept. It includes a hovercraft development discussion, a water-pressure brick breaker, and a vacuum pump example. The show explores how pressure works in various contexts like blood flow, rocket launches, and hydraulics, emphasizing its universal presence and impact on everyday life.

Takeaways

• 🧐 Pressure is a force that acts in all directions at once and can be exerted by gases, liquids, and solids.
• 🚀 Rockets fly due to the pressure exerted by the gases produced during combustion, which are expelled downwards, propelling the rocket upwards.
• 🩸 Blood flows through veins and air enters our lungs due to the pressure created by the heart and respiratory system.
• 🏗️ Hovercrafts float because the air pressure beneath them is greater than the pressure of the liquid (or ground) they are in contact with.
• 💧 Water pressure can be demonstrated by connecting a bucket of water to a hose and a cylinder, where raising the bucket increases the pressure.
• 🔧 The pressure exerted by a fluid (like water) can be transferred and used to exert force on objects, such as breaking bricks.
• 🔄 Pressure differences are utilized in various applications, including firefighting equipment like fireboats, which use water pressure for pumping.
• 🛤️ The concept of pressure is also applicable in everyday scenarios like walking on mud with snowshoes, which distribute pressure over a larger area to prevent sinking.
• 🌐 Atmospheric pressure is constantly acting on us and can be demonstrated with simple experiments like inverting a glass of water covered with a card.
• 🚗 Hydraulic systems, such as those in vehicles with adjustable suspension, operate based on the principles of pressure to lift or lower the vehicle.

Q & A

What is pressure and how does it relate to the properties of matter?

Pressure is a pushing force that acts in all directions at once, and it is a property of matter. It can act on air, water, or any substance.

How do hovercrafts utilize pressure to float?

Hovercrafts float due to the pressure created by the air being pushed down between the craft and the surface it hovers over, which lifts the vehicle.

What role does pressure play in the functioning of rockets?

Pressure is what makes rockets fly. The force of the gases expanding and pushing downwards creates the thrust necessary for lift-off.

How is pressure involved in the circulation of blood in our bodies?

Pressure, specifically blood pressure, is what makes blood go through our veins, propelled by the pumping action of the heart.

What is the relationship between pressure and the water-pressure brick breaker of science?

The water-pressure brick breaker of science demonstrates how pressure can be increased by raising a bucket of water, which increases the force exerted on the bricks due to the added weight of the water.

How does the pressure in a fireboat work, and what is its purpose?

Fireboats work on pressure created by pumps that can take in as much water as they are sitting in and pump it back out. The purpose is to fight fires by providing a high-pressure water stream.

What is the principle behind the experiment with the glass of water and the card?

The experiment with the glass of water and the card demonstrates atmospheric pressure. The air pressure in the room pushes the card against the rim of the glass, holding the water inside.

Why do mudshoes prevent sinking in mud?

Mudshoes, or snowshoes, prevent sinking by spreading the pressure over a wider area, thus not sinking into the mud as much as a smaller surface area would.

How does a vacuum pump create a vacuum, and what is its effect on pressure?

A vacuum pump creates a vacuum by pulling air out of a tube, which reduces the air pressure inside the tube. This lower pressure compared to the atmospheric pressure outside can hold objects in place due to the higher external pressure.

What is the significance of pressure in the context of a dam and electricity generation?

The pressure at the bottom of a dam is higher than at the top due to the weight of the water, which can be harnessed to spin turbines and generate electricity.

How does pressure affect the performance of a dart and why doesn't a penny stick to a dartboard like a dart does?

Pressure affects the performance of a dart because the tip of the dart focuses pressure on a point, allowing it to penetrate the board. A penny, having a larger surface area, spreads the pressure over a wider area and thus doesn't stick as effectively.

Outlines

00:00

🚀 Pressure: The Driving Force

This paragraph introduces the concept of pressure as a fundamental property of matter that acts in all directions. It uses the example of a hovercraft to illustrate how pressure can enable objects to float. The segment also explores the role of pressure in various phenomena such as rocket lift-off, blood flow through veins, and air entering lungs. A demonstration with a water-pressure brick breaker is conducted to visually show the effect of increased pressure due to the weight of water, analogous to the sensation of pressure change while diving.

05:01

💧 Exploring Water Pressure and Its Applications

The second paragraph delves into the practical applications of water pressure, particularly in firefighting vehicles like fireboats. It explains how fireboats utilize pumps to create pressure, which is essential for their operation. The paragraph also discusses the concept of pressure in the context of air pressure, demonstrating how it can hold water in a glass when a card is placed over it and flipped. A larger-scale experiment is attempted with a similar setup, emphasizing the role of atmospheric pressure in these demonstrations.

10:02

🛠️ The Science of Hydraulics and Vacuums

This segment showcases the use of hydraulics in a four-pump system, detailing how each pump contributes to the overall pressure that allows a vehicle to move vertically. The hydraulic system's components, including pumps and switches, are explained. The paragraph also touches on the concept of a vacuum, demonstrating how a suction cup arrow works by creating a vacuum that allows it to stick to a surface. A vacuum pump is introduced, illustrating how it operates by removing air and creating a vacuum that can support weight.

15:06

🌊 Harnessing Water Pressure for Electricity and Cutting

The fourth paragraph highlights the immense water pressure created by dams, such as Hoover Dam, and how it's used to generate electricity. It explains the pressure gradient from the top to the bottom of the dam and the placement of turbines to optimize energy production. The paragraph also explores the use of high-pressure water jets in cutting materials, emphasizing the speed and effectiveness of water under extreme pressure, even capable of cutting through metals like titanium.

20:06

🎶 The Ubiquity of Pressure in Daily Life

The final paragraph ties together the theme of pressure by demonstrating its presence in everyday activities, such as drinking through a straw, where atmospheric pressure plays a crucial role. It also touches on the pressure inside a soda bottle and how opening it releases that pressure. The segment concludes with a playful reference to the pressure inside a vacuum cleaner and the mess it can create, followed by a humorous outro that encapsulates the show's lighthearted approach to explaining scientific concepts.

Keywords

💡Pressure

Pressure is defined as the force applied per unit area. In the context of the video, it is a central theme illustrating how pressure acts in all directions and its various applications. Examples include the pressure in a hovercraft allowing it to float, the pressure difference that allows water to be pushed out of fireboats, and the high-pressure water used in water-jet cutting, which can cut through materials like wood and granite.

💡Inertia

Inertia is a property of matter that describes the resistance of any physical object to a change in its state of motion or rest unless acted upon by an external force. Although not directly explained in the script, inertia could be related to the theme of pressure in the sense that it talks about the properties of matter that are affected by forces like pressure.

💡Force

Force is any interaction that, when unopposed, will change the motion of an object. In the video, force is discussed in relation to pressure, as pressure is a type of force that acts upon surfaces. The script mentions how the force created by pressure can break bricks and how it's harnessed in various mechanical systems like hovercrafts and hydraulic lifts.

💡Hovercraft

A hovercraft is a vehicle that travels on a cushion of air, provided by the pressure of the air beneath it. The script explains that hovercrafts float because of pressure, which is used to lift the vehicle above the surface, allowing it to move smoothly over various types of terrain.

💡Vacuum

A vacuum is a space devoid of matter, such as air. The script uses the concept of a vacuum to explain the absence of pressure. It demonstrates how a vacuum pump creates a vacuum by removing air, and how atmospheric pressure can hold objects in place when a vacuum is present, as shown with the suction cup example.

💡Atmospheric Pressure

Atmospheric pressure is the pressure exerted by the weight of air molecules in Earth's atmosphere. The script mentions atmospheric pressure in the context of how it can hold a plastic plate against a tube when a vacuum is created, and how it pushes down on a milkshake in a cup, demonstrating the constant presence and effect of this pressure in daily life.

💡Hydraulics

Hydraulics is the study and application of liquids in motion. In the script, hydraulics is used to explain how a four-pump system can lift a vehicle, with each pump creating pressure that can move the vehicle up and down. This illustrates how pressure can be controlled and utilized in mechanical systems.

💡Water Pressure

Water pressure is the force exerted by water on the sides of a container or the pressure exerted by water at a certain depth. The script explains how water pressure is used in fireboats to pump water and in dams to generate electricity. It also demonstrates how water pressure can break bricks, showing the power behind this force.

💡Pneumatic Pressure

Pneumatic pressure, often simply referred to as air pressure, is the pressure created by an enclosed gas. The script touches on pneumatic pressure in the context of tools that use compressed air to operate, showing how air under pressure can be used to create a force that performs work.

💡Rocket Propulsion

Rocket propulsion is the process where a rocket pushes against the surrounding medium (usually air or space) to move in the opposite direction. The script mentions how pressure is what makes rockets fly, describing the concept of lift-off and how the pressure exerted by the rocket's engines allows it to overcome gravity and ascend.

Highlights

Pressure is a fundamental concept in science, affecting everything from the flight of rockets to the flow of blood in our veins.

Inertial properties of matter are crucial for understanding how objects resist changes in motion.

Hovercrafts demonstrate the principle of buoyancy, where pressure differences allow them to float on a cushion of air.

The pressure exerted by a fluid, like water, increases with depth due to the weight of the fluid above.

The concept of pressure is central to the operation of a hovercraft, where it allows for levitation and movement.

A simple experiment with water pressure can break bricks, illustrating the immense force that pressure can exert.

Fireboats utilize the principle of pressure to pump and expel large volumes of water for firefighting.

The pressure exerted by the atmosphere can be visualized through simple experiments with water and a piece of paper.

The pressure within a dam is harnessed to generate electricity, with the greatest pressure at the base where the water is deepest.

High-pressure water jets can cut through materials with precision, including metals used in aerospace applications.

The pressure of a gas inside a container, like a soda bottle, can be relieved by opening it, changing the physical state of the container.

Pressure is exerted in all directions and is responsible for the buoyancy of objects submerged in liquids.

The pressure of air molecules is what allows balloons to inflate and objects to float.

A vacuum is created by removing air, resulting in a pressure difference that can hold objects against a surface.

The pressure of a fluid can be harnessed to perform work, such as lifting heavy objects with a hydraulic system.

The pressure exerted by a fluid can be manipulated to create tools, such as a water jet cutter, that can shape and cut materials.

The pressure in the atmosphere is responsible for the behavior of gases and can be felt and measured.

The pressure of a liquid can be visualized by observing the behavior of air bubbles at different depths.

Transcripts

IT'S PUSHING IN ALL DIRECTIONS AT ONCE.

IT'S -- IT'S...PRESSU-U-U-U-U-U-U-RE!

WHOO!

♪ BILL NYE, THE SCIENCE GUY ♪

BILL NYE, THE SCIENCE GUY.

BILL! BILL! BILL! BILL! BILL! BILL!

♪ BILL NYE, THE SCIENCE GUY ♪

SCIENCE RULES.

♪ BILL NYE, THE SCIENCE GUY ♪

INERTIA IS A PROPERTY OF MATTER.

BILL, BILL, BILL, BILL, BILL, BILL NYE, THE SCIENCE GUY.

BILL! BILL! BILL!

T MINUS 7 SECONDS.

BILL! BILL! BILL!

♪ BILL NYE, THE SCIENCE GUY ♪

Announcer: BROUGHT TO YOU BY...

PRESSURE! AAAAAAAH!

WHOO!

WHOO-HOO!

WA-A-A-H!

HA HA.

PHEW! IT'S A HOVERCRAFT. IT'S IN DEVELOPMENT.

HOVERCRAFTS FLOAT BECAUSE OF PRESSURE.

NOW, PRESSURE PUSHES ON AIR, WATER, OR ANYTHING.

PRESSURE'S WHAT MAKES ROCKETS FLY.

Man: LIFT-OFF -- WE HAVE LIFT-OFF.

PRESSURE IS POWER.

PRESSURE IS A PUSHING FORCE IN ALL DIRECTIONS AT ONCE.

IT'S WHAT MAKES BLOOD GO THROUGH OUR VEINS...

[ HEARTBEAT ]

OR AIR COME INTO OUR LUNGS.

[ INHALES DEEPLY ]

NOW, TAKE A LOOK AT THIS.

IT'S OUR WATER-PRESSURE BRICK BREAKER OF SCIENCE.

THESE TWO BRICKS ARE THE KIND OF BRICKS

YOU MIGHT MAKE A SIDEWALK OUT OF.

AND OVER THERE IS A BUCKET OF COLORED WATER.

IT'S CONNECTED TO A HOSE,

AND THE HOSE IS CONNECTED TO THIS BIG, PLASTIC CYLINDER.

NOW, RIGHT NOW THE PRESSURE IN THE CYLINDER,

THE PRESSURE IN THE HOSE, AND THE PRESSURE IN THE BUCKET

ARE ALL ABOUT THE SAME.

BUT IF I RAISE THE BUCKET WAY UP,

THEN THE PRESSURE DOWN HERE WILL BE HIGHER

BECAUSE THE WEIGHT OF THE WATER IS PUSHING DOWN.

IT'S THE SAME WAY YOU FEEL PRESSURE ON YOUR EARS

WHEN YOU DIVE TO THE BOTTOM OF A SWIMMING POOL.

THE WEIGHT OF THE WATER MAKES PRESSURE.

NOW, THE PRESSURE IN HERE

WILL PUSH UP ON THIS BIG, PLASTIC DISK,

AND THE PLASTIC DISK HAS SO MUCH AREA

THAT IT WILL CREATE A LOT OF FORCE,

AND THAT FORCE WILL GO UP THIS METAL ROD

AND INTO THESE BRICKS.

OKAY.

LET'S HOIST THE BUCKET.

[ GRUNTING ]

[ DRUMROLL ]

[ CYMBALS CRASH ]

NOW, THE PRESSURE IS GOING DOWN THE HOSE

INTO THE BUCKET...

AND PUSHING ON THE BRICKS.

THERE.

[ CROWD GASPING AND CHEERING ]

IT BROKE.

YOU WANTED THEM BOTH TO FALL OFF?

Man: YEAH.

WELL, FINE. GET THEM BOTH TO --

WE CAN DO THAT -- TO FALL OFF.

THE WATER'S STILL COMING DOWN,

THE PRESSURE'S STILL PUSHING UP, AND BRICKS --

JUST ABOUT OUT OF WATER.

THIS IS THE FIRST ONE. SEE, LOOK -- IT BROKE.

BUT IT DIDN'T QUITE BREAK IN HALF

BECAUSE WE RAN OUT OF WATER. SEE? THAT'S ALL AIR.

[ GRUNTS ] THAT'S ALL AIR IN HERE.

NO, I'M NOT MAD.

I'M NOT GONNA, LIKE, GO NUTS OR ANYTHING.

YEAH! THAT'S --

YEAH! HA HA! THERE WE GO!

SEE? PRESSURE -- IT'S EVERYWHERE --

EVERYWH--

HEY, EVERYBODY, I'M SAMMY SUCTION,

HIGH-PRESSURE COMIC.

I'M HERE TO PUMP YOU UP. [ AIR HISSES ]

Narrator: WATER PRESSURE FALLS PERILOUSLY.

HOPE THAT THE FIRE CAN BE EXTINGUISHED IS GIVEN UP.

SO, TELL ME ABOUT FIREBOATS.

FIREBOATS ARE REALLY UNIQUE, BILL.

THEY SIT IN THEIR FIRE HYDRANT.

AS MUCH WATER AS THEY'RE SITTING IN,

THEY CAN PUMP THAT MUCH RIGHT BACK OUT.

FIREBOATS WORK ON PRESSURE, BILL.

THEY HAVE PUMPS. THE PUMPS MAKE THE PRESSURE.

THAT'S, UH -- THAT'S A LOT OF PRESSURE.

THAT IS A LOT.

WHENEVER THERE'S A FIRE, WE'RE READY.

UH, YOU'RE GETTING THE, UH, CAMERA.

Announcer: NOW IT'S TIME FOR ANOTHER EPISODE OF...

DATELINE -- THE WOODS.

WHEN IT COMES TO MUD, HIGH HEELS ARE DUDS.

TOO MUCH PRESSURE OVER TOO LITTLE HIGH HEELS

SINK ANY PLANS FOR A WALK.

TALK ABOUT DETERMINED -- SHE'S AT IT AGAIN.

BUT WHAT GIVES?

CERTAINLY NOT THE MUD UNDER HER SNOWSHOES,

OR SHOULD WE SAY "MUDSHOES"?

THEY SPREAD PRESSURE OVER A WIDE ENOUGH AREA

SO THAT SHE WON'T SINK.

THIS HAS BEEN ANOTHER...

YOU CAN SEE AIR PRESSURE

BY USING A CLEAR GLASS OF WATER LIKE THIS

AND A PIECE OF PAPER, A POSTCARD, OR A CARD LIKE THIS.

ALL YOU HAVE TO DO

IS PUT THE CARD OVER THE GLASS OF WATER LIKE THIS.

NOW FLIP IT.

THE AIR PRESSURE IN THE ROOM

PUSHES THE CARD UP AGAINST THE RIM

AND HOLDS THE WATER IN THE GLASS.

NOW WE'RE GONNA TRY IT WITH SOMETHING A LITTLE BIT BIGGER.

FILL IT WITH WATER.

NOW WE DO THE SAME EXPERIMENT AND PUT THE CARD OVER THE TOP,

AND IT SHOULD WORK,

'CAUSE IT WORKED ON THE SMALLER ONE

AND IT'S THE SAME EXPERIMENT.

WELL, WE'LL JUST DO IT.

[ DRUMROLL ]

UM...

DAD?!

WHAT YOU GOT HERE IS WHAT WE CALL A 4-PUMP SYSTEM.

THERE'S A PUMP GOING TO EACH CYLINDER.

EACH PUMP PUSHES A TREMENDOUS AMOUNT OF PRESSURE

THAT'S ABLE TO LET THE CAR GO UP AND DOWN.

THIS SWITCH WOULD BE FOR THE FRONT.

THAT'S WHAT OPERATES THE PUMP TO FILL UP THE CYLINDERS

WITH THE PRESSURE OIL.

THIS ONE WOULD BE FOR THE REAR.

THESE ARE LIKE EXTRA FOR THE SIDE-TO-SIDE...

...ONE TIRE IN THE AIR.

WE GOT 10 OF THEM WITH THIS FRONT-BACK, SIDE-SIDE,

INDIVIDUALS, AND MAKE IT TEETER-TOTTER.

AND, LIKE, PANCAKE -- WE CALL IT "PANCAKE" --

UP AND DOWN, FRONT AND BACK.

[ HORN HONKS ]

HYDRAULICS -- IT'S COOL, AND IT'S SCIENCE.

NOW WE'RE GONNA DO THIS ONE MORE TIME,

ONLY THIS TIME I'M GONNA GET SOME HELP.

COOL.

OKAY. SO, NOW WE PUT THE CARD ON TOP AND FLIP IT.

[ DRUMROLL ]

[ DRUMROLL CONTINUES ]

OH, MY --

[ BOTH LAUGH ]

PRESSURE ACTS IN ALL DIRECTIONS AT ONCE,

BUT WHAT IF THERE WERE NO PRESSURE -- NO PRESSURE AT ALL?

PLEASE...

...CONSIDER THE FOLLOWING.

PRESSURE COMES FROM MOLECULES --

TINY PIECES OF STUFF LIKE AIR OR WATER.

SO, THIS AIR-FILLED BALLOON HAS SOME PRESSURE IN IT,

BUT THIS BALLOON, WITH ALMOST NO AIR IN IT,

HAS ALMOST NO PRESSURE -- NO PRESSURE.

NOW, WHEN THERE'S NO PRESSURE -- NO PRESSURE --

WE SAY IT'S A VACUUM -- A VACUUM.

WE CAN MAKE A VACUUM -- VACUUM --

WITH THIS.

IT'S OUR SUCTION-CUP BOW AND ARROW OF SCIENCE.

[ FANFARE PLAYS ]

[ BOING! BOING! BOING! ]

[ FOOTSTEPS ]

SEE? THE ARROW HIT SO HARD

THAT THE SUCTION CUP FORCED ALL THE AIR OUT FROM UNDERNEATH IT,

SO THE AIR PRESSURE IN THE ROOM

IS PUSHING DOWN IN ALL DIRECTIONS

AND HOLDING THE SUCTION CUP AGAINST THE PLASTIC.

UNDERNEATH THE SUCTION CUP, THERE'S A VACUUM -- A VACUUM --

A VACUUM.

THIS IS A VACUUM PUMP, AND WHEN IT'S RUNNING,

IT PULLS AIR THROUGH THIS HOLE, THEN THROUGH THIS HOSE,

THROUGH THE PUMP, AND OUT HERE.

SO WATCH.

IF WE PUT THE PLASTIC PLATE

UNDERNEATH THIS BIG, PLASTIC TUBE,

THE VACUUM PUMP STARTS TO PULL THE AIR OUT OF THE TUBE

SO THAT PRETTY SOON I CAN LET GO -- I CAN LET GO.

SEE, THAT'S BECAUSE ATMOSPHERIC PRESSURE,

WHICH IS PUSHING IN ALL DIRECTIONS,

IS ALSO PUSHING UP ON THE BOTTOM OF THE PLATE.

SO PRETTY SOON THERE'S ENOUGH OF A VACUUM IT'LL HOLD ME UP.

OH, YEAH. SEE? NOT BAD.

SEE? I DON'T EVEN NEED THIS BOX.

[ LAUGHS ] SEE?

I'M JUST DANGLING HERE. I'LL SAY.

THE VACUUM'S HOLDING ME, THOUGH. MM-HMM.

NOW I'VE GOT TO, UH, TURN THE PUMP OFF.

LET'S SEE.

THERE.

THAT VALVE.

YEAH. NOW, AS THE AIR COMES BACK IN THE TUBE,

THE VACUUM GOES AWAY.

PRETTY SOON IT SHOULD LET GO, AND I'LL, UH --

AAAAAH!

[ TIMPANI PLAYS ]

Man: WE'RE CLEARING FOR LAUNCH.

WE ARE GO. 15 SECONDS.

THESE ARE GONNA BE THE FINS FOR THE ROCKET.

[ DRAMATIC MUSIC PLAYS ]

11...

[ DRAMATIC MUSIC CONTINUES ]

...10...

MY FINS ARE LOOKING PRETTY COOL NOW -- PRETTY COOL NOW.

...9...

FILL IT ABOUT A THIRD FULL.

...8...

READY FOR FINS.

IGNITION SEQUENCE START. ENGINES ON.

5...

[ DRAMATIC MUSIC CONTINUES ]

4...

3...

TIME TO LAUNCH IT!

2...

...1...

ALL ENGINES RUNNING. LAUNCH COMMENCED.

LIFT-OFF -- WE HAVE LIFT-OFF.

THE TOWER IS CLEAR.

GO, ROCKET!

[ CHILDREN SHOUT ]

[ DANCE MUSIC PLAYS ]

PRESSURE!

DOUBLE PRESSURE!

[ CHILDREN SCREAMING ]

CATCH IT! CATCH IT!

ROCKETS! ROCKETS! ROCKETS! ROCKETS!

OH, HI.

THIS TOOL WORKS ON PNEUMATIC PRESSURE.

AIR UNDER PRESSURE COMES THROUGH THIS HOSE.

IT PUSHES ON A DISK INSIDE HERE.

NOW, WHEN PRESSURE IS SPREAD OUT OVER AN AREA,

IT MAKES A FORCE --

A LOT OF FORCE.

[ LAUGHS ]

THAT GOT HER.

PIECE OF CAKE!

LET THE PRESSURE DO THE WORK.

PHEW!

[ DRUMROLL ]

[ CYMBALS CRASH ]

WHOA! CHECK IT OUT! IT WORKED.

[ APPLAUSE ]

I'M DOING A LATE-NIGHT EXPERIMENT...

[ CRICKETS CHIRP ]

WITH VACUUMS.

VACUUMS WORK WITH DIFFERENCES OF AIR PRESSURE.

[ CYMBALS CRASH ]

[ WHIRS ]

SEE? THERE'S A FAN IN THE MACHINE.

IT SUCKS UP ALL THE AIR INTO THE COMPARTMENT,

CREATING LOW PRESSURE.

BUT THE AIR OUTSIDE, WHICH HAS HIGHER PRESSURE,

WANTS TO FILL UP THAT SPACE.

AIR GOES IN THROUGH THIS TUBE,

SUCKING UP DIRT AND DUST AND OTHER NASTY THINGS.

IT SEEMS TO WORK PRETTY GOOD.

AAH! PRESSURE, PRESSURE, PRESSU--

NAILS GO INTO WOOD BECAUSE OF PRESSURE.

SEE, THIS END OF THE NAIL IS SHARP

AND HAS A VERY SMALL AREA,

SO WHEN WE APPLY A FORCE TO IT, IT MAKES A HIGH PRESSURE.

WATCH.

THE HIGH PRESSURE MAKES IT GO RIGHT INTO THE WOOD.

IF WE DRIVE A NAIL THE WRONG WAY,

WELL, THIS END HAS A BIGGER AREA,

SO, FOR THE SAME AMOUNT OF FORCE,

WE GET A MUCH LOWER PRESSURE.

WATCH.

SEE, IT DOESN'T WORK AT ALL.

ALSO, YOU HAVE TO USE A TOOL THAT CAN TAKE THE PRESSURE.

Woman: AND NOW...

[ CALLIOPE MUSIC PLAYS ]

OOH! TIME'S UP.

THE CORRECT ANSWER IS, "YES, AIR HAS PRESSURE."

HOW DO YOU THINK WE STUCK THIS PLUNGER OVER YOUR FACE?

[ LAUGHS ] THAT'S ALL, FOLKS.

WE'LL SEE YOU NEXT TIME ON "PRESSURE --"

[ UPBEAT ROCK MUSIC PLAYS ]

YOU GOTTA HAVE THE PRESSURE, MAN.

A DAM HOLDS BACK A LOT OF WATER,

AND THAT CREATES A LOT OF WATER PRESSURE.

IT WORKS LIKE THIS.

THE PRESSURE AT THE TOP OF THE DAM

IS LOWER THAN THE PRESSURE AT THE BOTTOM.

THAT'S WHY THIS ONE SQUIRTS OUT FARTHER.

SO WE PUT THE TURBINES,

THE THINGS THAT MAKE ELECTRICITY, DOWN HERE.

A LOT OF PRESSURE MAKES A LOT OF ELECTRICITY.

THIS IS A BIG DAM. IT'S HOOVER DAM.

IT ALL WORKS WITH PRESSURE -- WATER PRESSURE.

MY NAME'S PATRICK STIFTER. I WORK FOR A WATER-JET SHOP.

A WATERJET CAN CUT THROUGH WOOD...

LIKE A HOT KNIFE THROUGH BUTTER.

AND A GRANITE SLAB --

NO PROBLEM.

WATER'S PUT IN THERE UNDER PRESSURE

OF APPROXIMATELY 60,000 POUNDS PER SQUARE INCH.

UNDER THAT PRESSURE...

THAT WATER IS TRAVELING AT MACH 3.

THAT'S LIKE THREE TIMES THE SPEED OF SOUND.

EVEN STRONG METALS LIKE TITANIUM,

WHICH ARE USED IN AIRPLANES AND SPACECRAFT,

CAN BE CUT WITH A WATERJET.

THE HIGH-PRESSURE WATER ENTERS FROM THE TOP,

GOES THROUGH THE CARBIDE AT A VERY HIGH SPEED,

WHICH DRAWS THE ABRASIVE OR THE SAND THAT WE CUT WITH

THROUGH THIS WHITE TUBE.

THE WATER ACCELERATES THE SAND, PRODUCING A CUTTING TOOL.

Announcer: DATELINE -- THE DART BOARD.

A PENNY SAVED IS A PENNY EARNED,

BUT NOT WHEN IT COMES TO DARTS.

THE PENNY'S PRESSURE SPREADS OVER TOO LARGE AN AREA.

NO TRICK WILL MAKE IT STICK.

HERE'S A TIP -- A DART'S TIP FOCUSES PRESSURE ON A POINT.

STICK WITH DARTS. THEY STICK IN THE BOARD.

ISN'T SHE SHARP?

[ ACCORDION MUSIC PLAYS ]

[ CYMBALS CRASH ]

PRESSURE'S PUSHING IN ALL DIRECTIONS AT ONCE,

LIKE IN THIS AIR MATTRESS.

AIR MOLECULES ARE PUSHING EVERY WHICH WAY,

GIVING ME A NICE CUSHION IN WHICH TO SIT

AND PONDER THE PRESSURES OF SCIENCE.

HERE'S A BEAKER.

WHEN I TURN IT UPSIDE DOWN IN THE WATER,

THERE'S A BUBBLE OF AIR,

AND THE AIR PRESSURE IS HOLDING THE WATER OUT.

WATCH WHAT HAPPENS WHEN WE GO DOWN.

WHEN WE WERE AT THE SURFACE,

THERE WAS THIS MUCH AIR.

THE LEVEL IS RIGHT HERE.

BUT 5 METERS DOWN, THERE'S SO MUCH WATER PRESSURE,

IT'S PUSHING THE AIR UP.

THE SAME AMOUNT OF AIR NOW ONLY TAKES UP THIS MUCH ROOM.

IT'S PRESSURE PUSHING DOWN.

[ AIR HISSES ]

HI. PRESSURE IS WHAT FORCES AIR INTO BALLOONS

SO THAT THEY CAN FLOAT AROUND,

BUT HOW STRONG IS IT REALLY?

WELL, TRY THIS.

GET AN OLD MUG OR TEACUP

AND HOLD IT SIDEWAYS AGAINST A BALLOON WHILE YOU BLOW IT UP.

CHECK IT OUT.

THE BALLOON EXPANDED INSIDE OF THE CUP.

PRESSURE MAKES IT STICK.

[ WHIRRING ]

[ WHIRRING STOPS ]

THERE'S NOTHING LIKE A BANANA MILKSHAKE.

RIGHT NOW ATMOSPHERIC PRESSURE

IS PUSHING DOWN ON THE MILKSHAKE.

IT'S EVEN PUSHING DOWN RIGHT THROUGH THE STRAW.

BUT IF YOU SUCK THE AIR OUT OF THE STRAW,

THEN THE PRESSURE OUT HERE FORCES THE MILKSHAKE UP AND...

[ GULPS ]

INTO YOUR MOUTH.

AHH. NOW, IF YOU BLOW THROUGH THE STRAW,

THEN YOU HAVE TO OVERCOME THE PRESSURE OUT HERE

IN ORDER TO MAKE...

[ BUBBLING ]

BUBBLES.

[ BUBBLING ]

EXCUSE ME, MISS ABERCROMBIE.

IF YOU'D HOLD STILL FOR JUST ONE MOMENT HERE, WE'LL JUST --

[ TO TUNE OF SOUNDGARDEN'S "SPOONMAN" ]

♪ GAS PUTS PRESSURE ON THIS CAN ♪ ♪ FEEL THE PRESSURE WITH YOUR HANDS ♪

♪ PRESSURE ♪

♪ PRESSURE HELPS YOU HEAR THESE SOUNDS ♪ ♪ YOUR FEET PUT PRESSURE ON THE GROUND ♪

♪ PRESSURE ♪

♪ PRESSURE ♪

♪ ALWAYS PUSHING DOWN ON YOU ♪

♪ FEEL IT ♪

♪ LIQUIDS, GASES HAVE IT, TOO ♪

♪ FEEL IT ♪

♪ ALSO WORKS IN THIS VACUUM ♪ ♪ PRESSURE FILLS UP THIS BALLOON ♪

♪ PRESSURE ♪

♪ AND INSIDE A PARACHUTE ♪ ♪ AND PRESSURE FLOWS INSIDE THIS FLUTE ♪

♪ PRESSURE ♪

♪ PRESSURE ♪

♪ ALWAYS PUSHING DOWN ON YOU ♪

♪ FEEL IT ♪

♪ LIQUIDS, GASES HAVE IT, TOO ♪

♪ FEEL IT ♪

♪ FEEL THE PRESSURE WITH YOUR HANDS ♪ ♪ FEEL THE PRESSURE WHILE YOU CAN ♪

♪ PRESSURE ♪

WELL, THAT'S OUR SHOW. THANKS FOR WATCHING.

IF YOU'LL EXCUSE ME,

I'VE GOT SOME PATH-LINE PRESSURE DISTRIBUTIONS TO COMPUTE.

SEE YA.

PRODUCED IN ASSOCIATION WITH...

PRESSURE!

PLAY IT OUT, NOW!

OH, YEAH! UGH! YEAH!

I CAN'T TAKE THIS PRESSURE.

THIS IS A BRAND-NEW BOTTLE OF SODA,

AND IT'S HARD TO SQUEEZE

BECAUSE THERE'S HIGH PRESSURE INSIDE.

BUT WHEN WE OPEN IT, WE RELIEVE THE PRESSURE.

SEE?

NOW IT'S EASY TO SQUEEZE.

[ LIQUID GURGLES ]

I-I GOT A LITTLE ON MY COAT.

WE ALWAYS LIKE TO TRASH THE GUY.

THAT'S WHAT WE GO FOR WITH THESE GUYS.

WE LIKE TO GET THE STUFF ALL OVER THE GUY!

IT'S ALWAYS THE GUY!

IT'S ALL OVER MY COAT, MY SHIRT, MY T-SHIRT,

DOWN THE BACK OF MY NECK, INTO MY PANTS,

ALL OVER MY SOCKS AND MY SHOES!

-- Captions by VITAC -- www.vitac.com

CAPTIONS PAID FOR BY DISNEY EDUCATIONAL PRODUCTIONS