Practical Engineering - 2016-06-13
Engineers that work with fluids need a solid understanding of how they behave, and there’s one branch of fluid mechanics that plays a role in areas all across our lives. Whether you’re designing a water tower for a city or you just want to understand how those upside-down pet bowls work, you’ve got to know how to relate the depth and pressure of a fluid: hydrostatics. Thanks for watching! Website: http://practical.engineering Patreon: http://patreon.com/PracticalEngineering Music: Doctor Vox - Gold (https://youtu.be/VM-hX0BQf40) Music: Soft and Light - Electronic Senses
METRIC SIDE BY SIDE WITH IMPERIAL SYSTEM OH MY GOD I LOVE YOU
Yeah the metric system is better with powers of ten. Our number system is base 10. We could have a discussion if a base 12 number system would be better (it would). But the truth is we use a base 10 system."You are always dealing with degrees of precision." You are always limited by your equipment's precision, doesn't matter if it's imperial or metric.
"but it’s a PITA when you are building something to fit in the real world" I wonder why everyone in the world except the (former) british colonies use metric for everything if it such a pain in the ass. The truth is that the disadvantages of the metric system are negligible. The much easier conversion between magnitudes is much easier.
@TMoD7007 because they are used to it, it's natural to them. I think the metric system is much more natural cuz measurements are based on water: 1l of water are 10 cubic centimetres and weights 1kg. While imperial is completely random: 1gallon of water are 231 cubic inches and weights 8.34 pounds. Same with temperature: 0°c water is freezing, 100°C. While 0 Fahrenheit is based on the lowest temperature Daniel Fahrenheit could achieve in his lab.
@981porsche do do you think it would be easier if money was the same?
120 cents = 1 dollar or something like that
Quinn Eschenbach: Money doesn’t measure distance. What is half of 3/4? 3/8. What is half of 3/8? 3/16. Just double the denominator...or triple for thirds, etc. What is half of 75 cents? Doesn’t matter. No one ever needs to do that.
@Quinn Eschenbach The British system of money used to be 1 Pound = 20 Shilling, 1 Shilling = 12 pence, 1 penny = 2 half-pence = 4 farthing. That's also where the name of the penny farthing bike comes from. Oh, and just to make things more complicated, 1 guinea = 21 Shilling. See https://en.wikipedia.org/wiki/%C2%A3sd
I love this channel because he leaves nothing hypothetical. He builds and demonstrates everything and leaves us amazed. He works really hard on his videos
Most vloggers are lame and unwatchable because they're just $-grabbers
so what youre saying is that hes using puts sunglasses on practical engineering
Instead of watching cops chase biker videos, camp on this channel instead. Your future will thank you.
Who would watch biker and cops vids? Not me.
I'll do both my man
I'm not saying you shouldn't want to watch these videos. I really like them as well.
But. There are a few disconcerning statements bordering on Miss-information. Here are my corrections.
0:00. Which is ironic because I'm not sure at all if you have one.
Don't get me wrong. I love your channel.
But I was left pretty perplexed by your explanations.
Not of the explanations themselves. But how you could have gotten them wrong.!?!?!?!?!!!
1:42. The picture you're showing only has Potential and Static Energy. That is true.
But the picture you're showing Does NOT have the same amount of Energy anywhere it is measured from.
Due to its shape in the vertical. Meaning the higher the depth the lower the pressure.
I am assuming you wer referring to a closed and Static Energy pressurized system. But even then the picture you showed. Would still have greater Potential Energy pressure at the base. Then at the top.
The only way for the picture you showed to have the same energy when measured from anywhere. Is if it were a closed pressurized system. Completely outside the Earth's gravitational field.
That is the only time your statement could be correct.
7:15. I had to watch this part three times because I was shocked that you got it completely wrong.
Let's pretend for a moment that water in a vacuum does not immediately begin to boil.
or some kind of ionic liquid that takes a long time to boil off.
Or perhaps not a complete vacuum. But a very low kph PSI or bar.
If the room you were standing in while drilling that hole. Was somehow a complete vacuum.
The same exact thing would still happen.
Because it is NOT the air pressure pushing into the hole and pushing down the water.
It's the weight of the water creating a vacuum. That's sucking in the air.
And even if there was no air in the room. The water would still fall. Because you have broken the seal.
Despite there being no air in the room. There's no vacuum to prevent the force of gravity pulling the water down.
It is the vacuum that holds the water up. Even if there's no air to fill the empty space inside the jug.
I know this may seem unintuitive.
And if you are still confused by all means make an experiment to test this.
Where you replicate the same conditions as the original test.
But put it inside a larger box that is under a vacuum.
You don't have to drill. But you could just make it a removable lid. Attached the lid to a string. And then attach the other side of the string to a magnet. And then place another magnet on the outside of the container. Right behind the inner magnet. So that when you pull the magnet on the outside. It pulls the magnet on the inside. Which of course is attached to the string. Which is of course attached to the lid. So when you move the magnet on the outside. It pulls the lid off inside the container. Which is under a vacuum of its own.
And you will see the water level drop exactly the same. As the first test shown in this video.
7:25. The atmosphere is not pushing the water up.
it is the vacuum inside The jug that is holding the water up.
Literally the only thing the outside atmospheric pressure has to do with any of this.
Is the gas at the top of the water jug. Which technically still is under a vacuum.
But still has air pressure. However you will note it has less air pressure. Then the atmospheric air.
And that pressure will be by the same amount as the weight of the water pulling against the vacuum.
So when the water level in the dish gets low enough. Instead of all the water rushing out. The atmospheric air pressure feels the the lower air pressure at the top of the jug. And rushes in to fill it.
But because gravity has a direction. That does not apply from the top. Like if you drilled a hole at the top.
Which is why the water would still fall. If you were in a complete vacuum and then drilled a hole at the top.
For instance. If you put that dog bowl jug thing. In a vacuum. And The jug was completely full with no air in it at all.
And then started to remove water from the dish. Like a dogwood when they drink.
The water level in the tank would not fall. The dish would become completely dry.
And the water would still not fall. Until you drill the hole in the top breaking the seal and the vacuum holding the water up.
I know this seems unintuitive. But again. If you go ahead and performed that experiment as well.
It is the pressure differential caused by the weight of the water. That creates a vacuum that holds the water up.
But in the event there is no pressure differential. Because the water is full with no air in the jug.
And then that whole dog bowl contraption is put into a vacuum where there is no air.
It would cease to function. Until you broke the vacuum inside the jug. Despite the fact that the whole thing is inside a vacuum chamber of some kind.
And despite there being no air pressure. The water will still fall and overflow the dish. Until The jug is empty. Despite the fact that there is literally no air pressure anywhere in that process or equation.
So it is not air pressure pushing the water down. It is gravity pulling the water down.
And if what you were saying was correct. If you drilled a hole while the dog bowl contraption was under a vacuum. Then the water level would not fall.
And as we know it will.
So even if you cannot understand these concepts intuitively.
Realize that you are explaining it incorrectly.
I hope you found this correction useful and or helpful.
8:34. While technically the explanation you gave was not incorrect. Because those things are occurring. You just missed the main point about what's happening.
So yes there a whole bunch of little bubbles trapped on the walls and suspended in the water. Not in solution but suspended in the water.
As well as gases in solution in the water that come out of solution. And of course water itself that vaporizes and comes out of solution.
So you got all these gases rising to the top.
And that was your explanation as I understood it.
BUT. All of those gases are not cumulatively enough to displace that much water.!!!
liked by a lot.
So what gives.?
Why is that much water suddenly being displaced.
And that's the part you missed.!
It is because all those gases have also greatly expanded due to the very low pressure caused by the vacuum at the top.
At a normal 14.7 PSI. All those gases take up almost no room at all. To the point of thinking that the cylinder was completely full of water.
But as soon as the vacuum was applied. That is the amount by which that little bit of gas expands at very low pressure.
And would have continued to do so until the pressure equalized enough for the water itself to stop boiling out of solution.
And I'm not at all sure if you had that understanding. Otherwise you would have foreseen making the clear pipe at the top a much greater length.
So again your explanation is not accurate enough to be a very correct one.
I hope you find this correction helpful.
It was entertaining thoug. So you still get a thumbs up. 👍
This is proof that even science benefits from a well placed pair of googly eyes.
You definitively nailed it!
the part with the boiling at the end was really interesting, too bad it was so short. I wish you could describe it in more depth :-/
amazing,., i didnt know water boils at vacuum.
The boiling point of a liquid decreases with decrease in pressure. In vaccum water can boil at room temperature.
If you are on top of a mountain where pressure is lower than sea level, it will take more time to cook food than normal. Because water boils at a lower temperature than 100°c.
Pressure cookers cook faster because inside the cooker the water boils at a higher temperature due to increase in pressure than 100°c. Opposite to what happens in that tube.
the answer is a flip flop. temp=presh. presh=temp.
carnot cycle.
think heat cycle. heat pump.
right in front of your eyes.
my dad and a 5th. grade science book,and men, taught me this.
closed cicuetsnever = fe.
What most people know as boiling is actually a system in chemistry called vapor pressure. Every liquid as a specific pressure or temperature at which the intermolecular bonds in the fluid can no longer hold atoms on the surface back from equalizing the pressure difference. When you have an entire pot that’s on a rolling boil, the only places that the water is actually turning to steam is on the “surface” of the bubbles that form at the bottom and then quickly rise to the top. God I love chemistry...
Pv=nrt, learn about partial pressure also
I have a problem here. I want to give you a like for using SI units, your dog, and the fact that it was a good video, but can only give one. Which on would you like?
I would say metric. Even in the us we are taught in metric.
I would give equal points for the 3-legged dog with a positive attitude, and for the quirky brown cat who can't seem to figure out water. I also appreciate the inclusion of Imperial/SAE units, even though I was in school when we still thought that the USA would convert to metric in the 1980s.
Quite a conundrum .
Sorry but majority of population DOES NOT USE METRIC SYSTEM...Charles
Buddy Clem
The cat is curious but a little more skeptic.. She see the water wants the water but something is not quite right, the levels are not the same. And it's only got one life left. So she can't take chances.
your neighbors must be baffled by you
Go watch the "Smarter Everyday" video about the guy who builds giant Tesla Coils. One of them is 9 feet tall and throws 12 feet long lightning bolts. His neighbors must love him.
https://www.youtube.com/watch?v=_fTC_Ud_k3U
I'd be his new, grateful, sidekick best friend if he were my neighbour
@jmchez I would!
J Sev he's not gay, sorry mate struck out again. Alway a bridesmaid, never a bride lol.
I'm glad that you explained what those feet were in meters otherwise this vid wouldn't have made much sense for me :)
Soulsphere001 every customary unit is pegged directly off metric. On inch is 25.4 millimeters exactly.
One cubic inch is 16.387064 mL exactly.
One pound is 453.592 grams exactly.
This is set by law to the metric conversion act.
In fact the US is Officially metric. The reason why we have the customary units pegged to metric is for the provision to allow labels to carry customary units. Every label on every product in the us is marked in metric.
It's just that we have provisions to have labels in customary units.
Ah, that's good to know. Thanks for the information.
type conversions like this into your browser: "convert yard to meter" "convert 17 feet to centimeters" etc. "convert 27.5 pounds into kg"
It's funny how feet and meters both also mean other things. It makes hilarious misunderstandings almost inevitable.
@Sander vd Donk the contractors had always made their vehicles and components with the Imperial system, the probe crashed because NASA decided to start operating using a foreign system.
nothing's more inherently "scientific" about Metric, it's just as arbitrary except everything's standardized with zeroes so the simpletons and "Pop-Sci" fans don't get so confused.
This is the junior high school physics that you need to get in top exam senior high schools.
That poor doggie only has three legs! WAAAH!
All dogs have three legs, most have four.
The dog was super cute though, and deserves a hug.
Also its probably cool with just having three, seems to be happy!
Stop me if you've heard this one, a three legged dog walks into a bar...
I once had a 3 legged dog called Rover - ever time he barked, he rolled over.
@dwoodman26 Sounds like a limerick....
I once had a 3 legged dog called Rover
Who, whenever he barked, he rolled over.
Whilst barking one day
He rolled far away
And that was the last heard of Rover.
4:13 I thought I was entering an alternate dimension into a horror movie
yes
"Engineers working with fluids need a sold understanding..."
Haw.
Washboard Man Hahahah
"and I am on the roof, with a contraption of my own design" ... lol
"what if we could build a taller cat bowl?"
Even though Tanky McTankface is a vastly superior name, unfortunately that design was christened as Sir David Attenborough.
Get that man a funnel
lol
The kids here did a roof funnel, bad idea.. pressure was higher, which was un expected. ... Like turning on a garden hose shoved in the mouth.
cake.
@Cotronixco
web spider.
@Practical Engineering never thought I'd see 'lol' from a literal engineer.
"let's build a tank and find out"
Pulls up in scratch built t-34
Wow, where were you during my engineering classes! You Really make things easy to understand.
This is the reason why i'm subscribing this channel, simple explanation, easy to understand, and SCIENTIFICALLY ACCURATE.
"What if we could build a taller cat bowl???"
Holy moly, where'd all you people come from?! Thanks for subscribing!
Practical Engineering ..THANK YOU FOR THE INFORMATIVE VIDEO..MAKE MORE...
Do what you do, do it well, and they will beat a path to your door.
Simple answer really... your content is so good we want to be notified when new stuff drops
Its not boiling of water lol. Its dissolved air releasing with low pressure . You will understand if you de gass the water before experiment
I got here because I was binging on dam failure videos, which led me to you ,or rather the youtube algorithm brought me here. Have to understand hydraulics to understand dams and why they fail. I like the way you explain things and your voice is pleasant to hear.
LETS BUILD A TANK AND FIND OUT
PREACH~!
Great video! One thing worth mentioning is that trees manage to break this rule. Redwoods are far taller than your PVC pipe, but have Xylem (small tubes to transport water) running from the roots to the canopy. Only two things prevent the water from boiling ; a. the small diameter of the tube actually inhibits the state change and b. the perfectly smooth walls of the tubes do not have any imperfections to serve as a catalyst point or any defects to initiate a boil. The xylem can draw water using capillary action, and be absorbed at the top with no boiling.
maybe, because xylem in trees is not like as the "closed" pipe showed in this video. I think there is much pores in body of trees, so it can't cause vacuum effect at the top
Water doesn't boil in the tubes, but the atmosphere still wouldn't have the necessary pressure to take water from the roots to the leaves. Microscopic pumps maybe?
i don't know how the tree does it but maybe -
just like a multi-stage well pump - the tree can use the atmosphere to get 32 feet of water lift - fill a reservoir - and start another pump to lift another 32 feet
There's capillary effect in action. The surface tension of water and acute meniscus of water surface in thin tubes makes it rise great heights.
I'm thinking about that hard-hat shark
Tankie McTankface. I have got to like this video 🤣
cool - I finally understand this 'inches of mercury' thing. Thank you xD
I think A+++ Tom Scott for sending me here.
Dear Grady,
Please stop making such good videos, you'll put us out of a job.
Best regards,
Chemical engineers everywhere
Schools have become corporations for profit and don't teach well. You don't learn a lot at any given time and that causes ennui and loss of interest. Curious people are lacking there
6:19 three legged pupper! the one arm bandit!
6:08 : I really can't wrap my mind around that part
When I watch these videos I swear my IQ goes up by .05 atleast.
All we did in science class was take notes we seldom did any labs that actually helped us visualize the concepts.
6:03 "As long as it has the same height , it will always have the same pressure at the bottom"
So this would apply for tall people as well concerning liquid.
But for gas the pressure would be more or less the same?
I love this channel so much. You explain everything so well, and then do experiments, and then more explaining!
Plus your crafting montages are top notch!
WHERE WERE YOU DURING MY DEGREE!?!? Great video, keep 'em coming
I assume your neighbors know you? lol...
"what if we could build a taller cat bow?" wouldn't we need to build a taller cat?
Great video Grady!
Thanks!
Top ten anime love bonds that will never be broken
@Practical Engineering Your videos teach me so much, excellent quality. Great job.
7:04 i just realised, does that mean the level of the water on the open side would change depending on what altitude youre at, since youd be lowering the atmospheric pressure if you go higher?
=NOW I KNOW HOW TO CRUSH EVERYTHING WITH SMALL TUBE OF WATER
=HEHE
Holy shit I love how you made that imperial / SI screen. Vid is great as well, but honestly, this one takes the cake imo.
4:20 feels so much like an episode of how its made and I love it.
I just found this channel today. My favorite new channel. I love having great content to binge!
Love the flyaway shot at the end, with neither of you appearing to be holding a drone control.
Once I saw bi-plane I had to clean up my coffee mess, too funny.Great video keep them coming.
2:52 I love you
Great video (as always)! One question regarding your professional work: Do you use the imperial or the metric system at your workplace?
6:12 Blew my mind, thanks
Imagine just walking by and seeing him on a roof with a broomhandle and a bucket
dMb - 2016-06-17
Haha, "engineers who work with fluids need a solid understanding"
ahmd abdallah - 2019-09-05
What Is Islam?
Islam is not just another religion.
It is the same message preached by Moses, Jesus and Abraham.
Islam literally means ‘submission to God’ and it teaches us to have a direct relationship with God.
It reminds us that since God created us, no one should be worshipped except God alone.
It also teaches that God is nothing like a human being or like anything that we can imagine.
The concept of God is summarized in the Quran as:
{ “Say, He is God, the One. God, the Absolute. He does not give birth, nor was He born, and there is nothing like Him.”} (Quran 112:1-4)
Becoming a Muslim is not turning your back to Jesus.
Rather it’s going back to the original teachings of Jesus and obeying him
Wayne Smith - 2019-10-31
Hahahahaha
Elizabeth Frantes - 2020-01-08
I missed it, thanks for pointing it out! I don't get engineering humor . .. or engineering, for the most part. This dude is amazing, makes things so easy to understand. Even I get it when he shows you how things work.
Charles Robson - 2020-01-19
But it is correct, water is a solid, you can pressurize it but you can't compress it because its solid, so you do need a solid understanding of fluid dynamics. 🤣🤣🤣
Zach Lap - 2020-02-17
Sadly, They only have a gaseous understanding