Our professor of thermodynamics in the mechanical engineering department (Germany) suggested that we watch your video to understand the concept even more. Now I should thank you both :) Please feed us more of your bright work !
It is indeed a good brain teaser for thinking about conservation of energy. I love indisputable physical laws that intuitively feel at first like they break conservation. Knowing that fundamentally they cannot, teasing out why is always a great thought experiment. Definitely brain food for anyone studying thermodynamics.
There is one important detail missing from the description, which I think will confuse many viewers: the cylinder pressing down on the scale is a sliding plunger. We are not "weighing" the entire container and the water within, but rather the pressure exerted by the sliding plunger. (Most of the weight of the apparatus is supported by the clamp holding it in place.)
Every video I’ve seen about this paradox does not explain that. You assume they are weighing a flask and water. That would always be the same no matter the shape. If you put this on a scale, without supporting the flask, the weight would the same no matter the shape. Otherwise, every experiment would be different based whether you use a beaker or a flask and the size.
Katerina, please make more videos. Your talent at explaining counter-intuitive effects can be applied to many topics, and your presentation is a delight to watch. It's a powerful combination of a clear presentation and a counter-intuitive phenomenon.
A brilliant presentation. Educational and well metered. How refreshing to hear a lecture presented calmly with proper pauses in the dialogue rather than one long sentence delivered at high speed with all the full stops (periods) edited out as is common on TH-cam these days.
I generally did not comment on even a good video but your way of explanation made me do this. Very lucid and comprehensive explanation including all application. Last time also I saw some video to get a clear picture of this paradox but was not that much good. I am feeling like this time nothing left in this concept. Your students must be the luckiest one. Please keep uploading... such type videos to let us feel lucky too.
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you gte into hell. It is jail, but aint no bail". And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him. Repent of your sins and believe in Him!.
It may help to reduce the feeling of 'paradox' in the Hydrostatic Paradox if one remembers that there are several other basic ways of 'multiplying force', such as the lever, the screw, the pulley, and the gear-wheel. These all enable a relatively small application of force to achieve a great effect, e.g. using a small weight to lift a much larger weight. This is not magic: we are not getting something for nothing. There is a trade-off between the strength of the force generated as the 'output' and the distance over which the force of the 'input' has to be applied to achieve the effect. For example in the case of a lever of the standard kind (with the fulcrum between the force and the load), a force of one kilo can only lift a load of ten kilos by moving through ten times the distance. In the case of a hydraulic press and similar devices, the trade-off is between the distance through which the 'input' fluid moves as compared with the much smaller distance through which the 'working' end of the press moves in the same time.
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you get into hell. It is jail, but aint no bail". And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him. Repent of your sins and believe in Him!.
Similarly, in the static case, in which the same 50g mass balances different volumes of water, the trade-off is accomplished by the extra work of lifting the water to a higher height.
This is exactly what I came to comment. I wish it had been mentioned while bending the aluminum bar. The intuitive explanation is trying to push on a door 12" from its hinge a distance of 1" vs trying to push a door 36" from its hinge for 3". The same work is done, but the second method requires much less force. Work = Force * Distance
@@GoodLifeMedicine But isn't it true though that all three vessels had water surfaces at same height, not different ones? and it is actually the key was the column height arethe same, not different? I guess I'm confused. I thought the lesson was the water being up to the same top level? thx sorry if wrong
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you get into hell. It is jail, but ain't no bail". And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him. Repent of your sins and believe in Him!.
From my experience in college (u/g in IS aka MIS, MBA, and ~50% of law school) most of the professors do a "meh" job of presenting material. They could learn a *lot* from professors like her. I get the impression that she would not mind if physics professors (including the ones who teach watered-down physical science to non-technical majors) were to copy and adapt her techniques.
You're right. This wasn't explained in "fluid mechanics 1 class". This was fully explained in basic high school physics. "Why does an arrow go into something when a basketball doesn't? I don't understand. I need it explained to me in terms of celebrities stepping on me" Gott im Himmel. We are doomed. Octopus for president.
I am 64 years old where 40 I worked in Hi-Tech industry (currently architect of liDAR system). I am so glad to say that I enjoyed every minute of this video. There are several reasons: First I learned!! Your explanations are so clear and I feel i understand anything you said. Another important thing (which might look insignificant but for the rest of the world it is) your way of speaking (diction and articulation) enable people which english is not their mother tongue to understand every word. Please continue!! thank you very much .
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you gte into hell. It is jail, but aint no bail". And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him. Repent of your sins and believe in Him!.
I'm a civil engineer, and when I used to design shutters to contain wet concrete, for example to form tall narrow walls, the builders on site used to ask me, 'why is the pressure so high? theres only a small amount of concrete going in'. I just used to say thats what the hydrostatic pressure calculations give me, but i couldnt quite answer exactly why. They used to think i was going over the top by putting in reinforced joists on the shutter panels to withstand the forces. I'm glad I've finally found the answer to this question. I'll send the guys on site the link to this video next time they start questioning my formwork designs.
I used to design instruments for industrial use and there's specifications for water resistance. One was a spray hose but that required an equivalent fire-fighter 2 inch size (to large) or a depth of six feet (a large volume of water). What I used was to take a 50 gal drum 34 inches high, not tll enough. So I put a cover on it and screwed a 3ft 2in pipe in the fill hole and got my 6 feet deep of pressure to test my instrument.
The explanation is simple. It is a combination of the previous two examples. The upper surface of the slanted tube exerts a downward force that adds weight and the lower surface exerts an upper force that reduces weight. If you apply the virtual volume concept (imagine a fluid mass reaching outside the surface to the level of the fluid) you will realize that the downward force is slightly bigger than the upward one. This is because the upper surface is slightly bigger than the upper ward force which means that an additional weight is applied precisely equal to the weight of the slanted volume of the fluid
Water has a head pressure of about 0.43 PSI per foot of height. So, a 75ft column of water has a head pressure of about 32 PSI. That's about 2 atmospheres. 9:17 You also have to pump 11 times the volume of liquid through your pump. It is very much like lever arms except we are now talking about volume of liquid. The small piston moves 11 inches for every inch the large piston moves.
This exactly. I thought I had forgotten how to math. Great video just wish they had taken more time to explain the math so I could figure out what I was doing wrong or they could see they messed up the math. I was using 14.7 psi for every 33 feet of seawater(.445 PSI/foot but close enough to .43 for fresh water). The one atmosphere of 14.7 PSI would be essentially the same at the top and bottom of tube and all around the vessel so it cancels. I always wonder if I am crazy when someone smarter than me makes an arithmetic error or misplaces a decimal or confuses units. Still occurs to me that we could be completely wrong and missing some subtle aspect of this.
@@mrous1038 Let me teach you an arithmetic trick. You will notice she is dividing 1,250 by 5 to get 250. Division by 5 is the same as multiplying by 2 and dividing by 10. 1/5=2/10 so the trick is this, multiply the number by 2 and move the decimal 1 place to the left (division by 10). in this case 2 x 1,250 = 2,500 move the decimal to get 250.
As long as you use proper units, it is calculated as d*g*h, where d is the density of the fluid, g is acceleration of gravity, h is the height of the tube. If you use IS units (Meters, seconds, kilograms...) you need no further conversion. Else, you need some conversions.
And tbis is assuming the tube is large enough that capillary force doesn't become significant ( assuming the total volume is fixed at 1 liter, the height and cross sectional area would be inversely proprtiona) . Once the tube is small enough there would be no additional pressure in the flask.
Years ago I was introduced to these and many other laws of fluid dynamics and pressure through SCUBA diving. These really come into play when diving deep and become even more complex when diving deep at altitude. All that aside, I love your explanation here and how lead your students from the known to the unknown. Very well done!
Diving deep at altitude? Now that's a topic I've never seen discussed on TH-cam. I've only ever seen divers as folks who go in the ocean, but there are enormous structures built at altitude that would need divers at some point, I think of dams here. Thank you for that. I'm happy you learnt your lessons well enough to still be 'sucking oxygen' after all this time. Long may it be so.
This is a great video series to understand the laws of hydrostatics. It was fun to watch and wants me to grab a hose and barrel for further "research" :-). As it's addressed to a broad US audience, I understand the usage of units like psi, lbs and in². Nonetheless it could have been even better if you additionally had added the common SI units for your international audience.
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you get into hell. It is jail, but aint no bail". And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him. Repent of your sins and believe in Him!.
@@neaworld3960 The wages of sin [i.e. death] increase expositionaley, when stacked on top one another! As apposed to the free gift of God's everlasting life! [IF?] you can believe?
@@stevemitz4740 hiii . I do suppose you mean that God cant save, however, He vcreated the universe, (which would not exist without a creator, and the evolutionary theory fails to prove the non existemce of a creator) im sure His Only Son's sacrificial death on a wooden cross where He took the wrath of God for you, because of sin, upon Himself. Do you know how much Jesus loves you? Neither angels, nor darkness can separate you from His bountious love towards you. GOD looks upon you with compassion, and me too, for though we " all have sinned and fallen short of (His Holy standard) the glory of God, God seeks to turn you back to Him. He loves you and created you to be happy, fruitful and joyous in communion with Him. Trust me.. if it were not for the love of God, i would not be telling you these things today, because naturally I am a mean-kinda gal and God Himself has poured His love into my heart. Añl He is asking you to do today is turn from your sin and to Him. He will be right there for you. He will never fail you. I know past relationships have failed you, but " [God] will never leave nor forsake thee". He won't fail, he won't walk out when things get bad, ; He will be there. Amd He has been threre your whole life. You just need to open the door [of your heart] to Him today.
The best way to explain hydrostatic paradox! Even though her way of talking is slow....it gives us time to get the idea into our brain....I appreciate her examples with different shapes of vessels containing same height of liquid...the last one may seem really tricky but if you look close to it...you can figure it out that even though the liquid tis not directly under it's base....as pressure act in every dirction...we can get the vertical liquid column in a zigzag way...thank you so much for uploding such a video...I learnt so many things....keep uploading...wish you the best.
Very clear and lucid but my favorite bit was to introduce me to someone I had never heard of, Simon Stevin. One of those ridiculously brilliant people all the world ought to remember beside Kepler and Galileo.
Wow, I do not say this lightly. This video just blew my mind. How did such basic physics escape me for so long? Excellent video, I am, of course, subscribed with notifications turned on, and thumbs up!
Excellent!! As far as I know, the hydraulic lift (not the hydraulic jack) used to lift vehicles doesnt utilise the force multiplication effect. The cylinder piston under the vehicle is actually of lower area and is used to move the vehicle up over a longer distance. The larger area cylinder piston is the one where pressure is applied on a barrel of oil using an air compressor. It requires more force, but that is achieved using air. So it works on Pascal's principle, but contrary to what is commonly explained for the hydraulic lift, the car is not lifted by force amplification.
Great video, I also really appreciated the addition of biology into a physics video. It really shows that their is connection between the sciences, and it gave a great example of applied physics.
I totally love the reference to animals and the comparison. These days I reckon its pretty critical to help students realise connection to the natural world, rather than just mechanics.
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you gte into hell. It is jail, but aint no bail". And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him. Repent of your sins and believe in Him!.
*_Here the real (math) paradox_* for me at 0:20 => the height of the water in the straw was said to be 75 ft. I was taught that a height of approx 34 ft of water produced 1 bar or (which is the same thing) 1 atmosphere of pressure. So, 75/34 = 2.2 bar = 2.2 atmospheres. Now 1 bar or 1 atmosphere of pressure is approx *_14.7 psi_* . Therefore 2.2 x 14.7 = *_32.4 psi_* ??? How does this pressure become around *_45 psi_* inside the barrel, as stated in this video? [another way of saying it, in order to have 45 psi water pressure, its height must be 45/14.7 x 34 = *_104 ft_* .]
As a free diver, you can really feel hydrostatic pressure once you dive down -30'. I'm not sure if I even hung out at -60' but at the negative 40'-50' range you really feel the hydrostatic pressure in your internals. On the bright side, If you want to look skinny, take a selfie at -60'.
Crystal Clear explanation, while watching the video by itself is very pleasant the way it is made and presented by this lady. One would not expect that a subject like this could be so interesting
I have seen a turbine at a off-grid location that generates electricity powered by hydrostatic pressure. Water is ejected at great pressure from the bottom of a pipe that is laid in a stream bottom with its inlet some elevation above the outlet. The pipe must be made progressively thicker from top to bottom to hold the pressure.
This video made sense of a phenomena that I've been aware of for quite some years but never actually understood. Thank you for such a succinct and understandable explanation! 👍
@@kaboom-zf2bl the human heart pumps about 19 kPa of pressure, we can assume if the brontosaurus heart is 2.3 times bigger than a human heart it pumps 2.3 times as much, meaning they pump at about 43.9 kPa of pressure.
@@Doofenshmirtz1088 consider a brontosaurus is 30 feet tall ... we are 6 feet .. so 5 times bigger ... taking the inch and half and increasing it drastically ... a giraffe at 11 feet is at 3inches ....so a 9nch muscle s expected or the size of an adult head at roughly 9inches
That's assuming a brontosaurus regularly held its neck up like a giraffe. If it only did so in short intervals, it could live with less blood pressure because its resting position is lower. Still far greater than a giraffe though!
In so many beautiful ways nature always squares up the books. Work is force over distance. Work expended on the small cylinder in a hydraulic jack has to match the work accomplished at the larger piston. A small force over a large distance (many repetitions of the jack handle) has to be the same work done at the large cylinder. Because it can't move as far for each cc of fluid, the large piston has to do so with far greater force than the small cylinder. I deeply regret not paying better attention in school. Physics is wonderful. Thank you for the food for thought.
Dr. Visnjic: Thank you. Great video fun and great learning I thought I knew, and very well presented. That was nice to give credit to Mr. Stevin. I had some minor notes/questions, sincere apologies if they are obvious or wrong. Pls forgive the numbering, its just for me to attempt being organized! 1. The point about all points in a fluid being at same pressure isn't quite right, is it, under gravity, since the fluid has mass, if the vessel is not all at one height, isnt that correct. 2. The pressure in the vessel also wouldnt be equal everywhere, if the fluid were moving, say if the fluid was rotating in the vessel, or convecting. or vessel is in noninertial frame? 3a.. It would be great to understand the role of atmospheric pressure here, especially if it were low, say down here vapor pressure; and if gravity were much higher; 3b. and how the results would be different if the vessels tops were not open to the air. 3c. and Especially,, with the cool barrel experiment, what if the top of the 150 ft tube was sealed, before pressure applied at the barrel. what would happen, at that height,150? feet? I guess all the gases would come out of solution at the top; then the fluid water at top would starts to vaporize in near vacuum.and the plastic tube would shrinks everywhere, and the barrel still explodes? 4. And if I had a wishlist, I would love to understand the relation of static pressures, such as shown shown here, to the vessels' "capacities, like a battery, and the output Impedances" or what an EE like me would call it, (dynamic heads?)say of the different shapes as here and the same initial flluid height height, for instance the martini 630g glass vessel I would say has high capacity, initially at least, and llow output impedance to flow out of its bottom aperture, while the one with the thin top, would have low capacity and high output impedance to flow out of it's bottom aperture? Thanks for your work and cool demos, and any consideration, Best regards,
this is an extremly amazing video. i´ve had very good physics teachers throughout my life but this is top level even amongst them. keep doing those videos.
Thank you for the amazing video. Just one question about the third container, we knew intuitively that the water will seep out and your explanation was based on this statement. If there was no column of water above the container the water would not have seeped out, could you please give a more detailed explanation on how is the pressure transmitteted from the vertical column of water to the rest of the container?
I had this principle become important when using a direct reading pressure gauge to measure oil pressure of a very large helicopter (CH53E) transmission. The gauge was on a long hose which could be moved about 6 feet below the bottom of the transmission. The pressure increased a few ( 1 or 2) psi when the gauge was moved to the floor of the helicopter.
@@Anksh0usRacing No. The cable or more correctly the hose and direct reading pressure gauge are not part of the aircraft. The normal pressure sensing device is a pressure switch mounted on the transmission. We were using the direct reading gauge as part of a test.
It's 2,81 kg/cm^2 :D You're welcome. You: 1:06 "made the mistake of writing in Dutch not in the scientific language of Latin" Me: "made the mistake of using imperial units instead using the scientific SI units" :D 1 mile = 1760 yards 1 km = 1000 meters Correct me if I'm wrong. Nevertheless it's a GREAT video.
OMG, best comment ever ;) I'm totally with you. It's not like imperial is bad and the end it's just a set of units and numbers that you learn as the kid and got used to it. What is bad is inconsistency that it produces. For example all electric and magnetic laws are based on SI International Measurement System with uses metric units (kilograms, meters). Volt is at the end (kg*m^2)/(A*s^3), ohm is at the end (kg*m^2)/(s^3*A^2). Not using metric system which is International Standard or using Imperial units mixed with metric (like wire resistance Ohm per feet, blaaahh) is a tumor on measurement consistency.
Thanks professor Katrina, I never seen such beautiful professor giving very simple yet clear explanation. I wish we could have applied real time calculations as well.
@Physics4Life this video is awesome! I learned a lot. One thing I would appreciate though is if you could give a brief answer/explanation to your question about the slanted water tube mentioned at 7:48 of the video either in the description or here please.
I think it is because as the water is pushing against the walls of the slanted tube the vertical component of the pushing force increases the weight on top of the balance and so we need 50g weight to balance it even though most of the water is away from the stopper Just an assumption tho😕
@@summerr0503 do you think that would happen in all tube like containers? Like if you had a silly straw like shape? Would the pressure only accumulate on the vertical axis of the water? And would the walls contain the weight like those in the examples?
@@alanbaraka9800 For tube of any shape the weighing machine will measure the weight acting directly on it, as for the pressure in any weird shaped tube need not be acting perpendicularly over the machine(as in the third case) so the weighing machine only measures the force generated by the vertical component of pressure exerted by the water, but the entire weight of water is indeed supported by the walls of the tube
Slanted water filled upto same vertical height will also lift only 50gm. This is because.. Lifting up force by the lower surface of slanted glass is cancelling some of the pushing down force by the upper surface of slanted glass.
for the slanted one, one of the sides exerts a reaction force down while the other up so the pressure would just be the same as the others at the same height?
Physics made easy and fun. I wish my teacher was able to explain physic phenomena this easy, interesting, and fun. I was shopping when another customer asked for a suction pump that was supposed to suck water up 12 meters. The clerk told him that such pumps don't exist. The customer was stressed and visibly disappointed and began protesting this. Then I said the clerk was right. Such pumps doesn't exist and are impossible to made. The customer was even more stressed. Nobody said a word for at least half a minute. Then the clerk said to the customer that he could buy a pump that could _pump_ water up 12 meters. Physics is just fun!
As a geologist I learned that (fresh) water exerts a pressure of 0.433 pounds per square inch per foot. Therefore a tube 100 feet high would exert a pressure of 43.3 psi at its base, regardless of the diameter of the tube. This was critically important in assessing the weight of fluids needed to withhold fluid influxes in a borehole.
ya I really hate it when someone gets it all so wrong, but hay kept the kids quiet, and looked good. I had to thumbs down as soon as she said 75 ft head of water was 45 psi ???????WHAT
Stimulatingly delightful video. Relearned, with better clarity, few 101 concepts, grateful for that. Appreciate the effort that went into its making, by the Professor and the entire team. Forgive my pedantic quibble though; it took me some time to understand the weighing set-up. Dunces like me could benefit had the stopper and lower tube coupling been further elaborated. Save for this petty nitpick, the video undoubtedly is purely edifying. An application that comes to my mind is the use of surge tanks to relieve immediate pressure surges, like due to the closing of valves, somewhere in the pipping system, which by Pascal's law will be equally transmitted throughout the system.
Yeah! second this. I can understand the pressure in the other containers but the angled column seems as if it would be reacted against by the glass and not the lower plate, however this is not the case
Hooollyyy this deserves more views!! Algorithm pls boost! This is by far one of the best academic-education videos I've seen. I've long believed that it's the practical demonstrations most students need in order to truly appreciate the sciences. Thank you
Air is also a fluid and consequently follows these laws too. When we examine the water or air-flow through a propellor we find that there is a reduced pressure ahead of the propeller and an increased pressure behind it. This provides the generated thrust but the kinetic energy in the accelerated flow behind the propellor is wasted and the propulsive efficiency of a propellor would be greater if the flattish disk (or actuator-disc) of rotation of its blades could be replaced with something else. Were a centrifugal fan used instead of an actuator disc, to accelerate the water or air-speed and then the resulting radial flow turned to pass behind and parallel to the axis of this fan's rotation, this loss in propulsive efficiency would be partly avoided.
That video on the giraffe will explain the pressure regulating mechanism that prevents the giraffe's head from exploding when it lowers it below the heart to drink. Fascinating stuff.
i've paused the radio program on Pascal i'm listening to, to see if some of his stuff was here on TH-cam.. i'm looking forward to getting back to the program but so pleased and grateful for this.. thankyou for sharing 🙂 x
In 1977 at Colorado College i was lucky to take a physics demonstration class by visiting Prof. Julius Sumner Miller, Disney's Physicist. For 2 hours a morning for 3 weeks he did demonstrations and we had to write a notebook with our explanations. It was an amazing class. Dr. Brown from Back to the Future wasn't near as crazy as JSM!
Ms. Visnjic, thank you for sharing this video, which answered a question I had about aerostatics. I'm looking forward to using the principle and learning more.
Here is a thought: Fluids are typically thought of as incompressible, but that isn't really true. Fluids do compress under pressure, although much, much less than gasses do. Still, if you pour water into a full barrel through a tall skinny tube, a little bit of that water will actually be forced into the barrel by the pressure of the water above it. And even though the amount is small, because water is almost incompressible adding a small amount of water to an already full barrel will increase the pressure enormously. For me this explains why the width of the tube doesn't matter. The barrel breaks when a sufficient volume of additional water has been forced into it, and you can eventually add any amount of water through a tube of any width. If you are using a needle thin tube, the level of the water at the top of tube will drop as a tiny amount of water from the bottom gets forced into the barrel. This probably won't be enough to break the barrel, so you will probably need to top off the tube repeatedly. But eventually, even through a needle thin tube, you will have forced enough additional water into the barrel to break it. I find this a very satisfying explanation -- what do you think?
Seeing no one responded to your question, I will. First, your statement that adding a small amount of water to an already full barrel will increase the pressure enormously is a bit ambiguous so my interpretation of the statement is unsure. And a needle-thin tube I think would be too thin to work. To try to understand the behavior based on the accepted hydrostatic principle, that the pressure / force exerted by the liquid against the container walls is based on the hydrostatic pressure rather than liquid's mass, is wrong; the pressure / force exerted is actually based on the liquid's mass which is very easy to prove both with mechanics and experimentally.
this was soooooo cool, you explained it so well that i understood something that i have been ponderin (just in my head from time to time) about from time to time ever since i know about myself
Our professor of thermodynamics in the mechanical engineering department (Germany) suggested that we watch your video to understand the concept even more. Now I should thank you both :) Please feed us more of your bright work !
It is indeed a good brain teaser for thinking about conservation of energy. I love indisputable physical laws that intuitively feel at first like they break conservation. Knowing that fundamentally they cannot, teasing out why is always a great thought experiment. Definitely brain food for anyone studying thermodynamics.
@@amarissimus29 "A picture is worth a thousand words."
what was the answer on the angled one?
That is so awesome 👌 what a great compliment! She is amazing.
There is one important detail missing from the description, which I think will confuse many viewers: the cylinder pressing down on the scale is a sliding plunger. We are not "weighing" the entire container and the water within, but rather the pressure exerted by the sliding plunger. (Most of the weight of the apparatus is supported by the clamp holding it in place.)
Yes, the essence of the paradox cannot be fully understood without this important detail.
Every video I’ve seen about this paradox does not explain that. You assume they are weighing a flask and water. That would always be the same no matter the shape. If you put this on a scale, without supporting the flask, the weight would the same no matter the shape. Otherwise, every experiment would be different based whether you use a beaker or a flask and the size.
Some vessels could be the same volume but higher surface area so more weight overall ❤
So the sliding plunger is only directly weighing the column of water above it, right? My head just literally exploded. I'm exploding right now
@@TravisTellsTruths Same volume would mean the same weight.
One of the best science videos I've ever seen.
Indeed
Really, true ... I agree
this isn't a science video. science videos use the metric system
@@Sebastian-hg3xc
The grass isn’t wet.
The grass is wet when it rains.
Katerina, please make more videos. Your talent at explaining counter-intuitive effects can be applied to many topics, and your presentation is a delight to watch. It's a powerful combination of a clear presentation and a counter-intuitive phenomenon.
A brilliant presentation. Educational and well metered. How refreshing to hear a lecture presented calmly with proper pauses in the dialogue rather than one long sentence delivered at high speed with all the full stops (periods) edited out as is common on TH-cam these days.
I generally did not comment on even a good video but your way of explanation made me do this. Very lucid and comprehensive explanation including all application. Last time also I saw some video to get a clear picture of this paradox but was not that much good. I am feeling like this time nothing left in this concept. Your students must be the luckiest one. Please keep uploading... such type videos to let us feel lucky too.
Absolutely correct
I wuold add: a perfect english pronounciation. An ideal video for a CLIL lession
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you gte into hell. It is jail, but aint no bail".
And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him.
Repent of your sins and believe in Him!.
Yes, so true!
Next time just type, "Hey babygirl..."
Not only what the content well organized, but her enunciation and steady pace make her easy to understand when English isn't your first language.
It may help to reduce the feeling of 'paradox' in the Hydrostatic Paradox if one remembers that there are several other basic ways of 'multiplying force', such as the lever, the screw, the pulley, and the gear-wheel. These all enable a relatively small application of force to achieve a great effect, e.g. using a small weight to lift a much larger weight. This is not magic: we are not getting something for nothing. There is a trade-off between the strength of the force generated as the 'output' and the distance over which the force of the 'input' has to be applied to achieve the effect. For example in the case of a lever of the standard kind (with the fulcrum between the force and the load), a force of one kilo can only lift a load of ten kilos by moving through ten times the distance. In the case of a hydraulic press and similar devices, the trade-off is between the distance through which the 'input' fluid moves as compared with the much smaller distance through which the 'working' end of the press moves in the same time.
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you get into hell. It is jail, but aint no bail".
And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him.
Repent of your sins and believe in Him!.
Similarly, in the static case, in which the same 50g mass balances different volumes of water, the trade-off is accomplished by the extra work of lifting the water to a higher height.
This is exactly what I came to comment. I wish it had been mentioned while bending the aluminum bar. The intuitive explanation is trying to push on a door 12" from its hinge a distance of 1" vs trying to push a door 36" from its hinge for 3".
The same work is done, but the second method requires much less force.
Work = Force * Distance
@@GoodLifeMedicine But isn't it true though that all three vessels had water surfaces at same height, not different ones? and it is actually the key was the column height arethe same, not different? I guess I'm confused. I thought the lesson was the water being up to the same top level? thx sorry if wrong
@@jwgmail The professor did note leverage, noting that the press lever was giving I think a 4:1 advantage
This is exactly the part of the explanation that is left out in our fluid mechanics 1 class. Thank you!
That's exactly why I did this! :)
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you get into hell. It is jail, but ain't no bail".
And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him.
Repent of your sins and believe in Him!.
From my experience in college (u/g in IS aka MIS, MBA, and ~50% of law school) most of the professors do a "meh" job of presenting material. They could learn a *lot* from professors like her.
I get the impression that she would not mind if physics professors (including the ones who teach watered-down physical science to non-technical majors) were to copy and adapt her techniques.
@@Physics4Life Would you be alright with other professors copying and adapting your techniques?
You're right. This wasn't explained in "fluid mechanics 1 class". This was fully explained in basic high school physics.
"Why does an arrow go into something when a basketball doesn't? I don't understand. I need it explained to me in terms of celebrities stepping on me"
Gott im Himmel. We are doomed. Octopus for president.
I am 64 years old where 40 I worked in Hi-Tech industry (currently architect of liDAR system). I am so glad to say that I enjoyed every minute of this video. There are several reasons: First I learned!! Your explanations are so clear and I feel i understand anything you said. Another important thing (which might look insignificant but for the rest of the world it is) your way of speaking (diction and articulation) enable people which english is not their mother tongue to understand every word. Please continue!! thank you very much .
this is the best way to explain fluid statics . thoroughly enjoyed it
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you gte into hell. It is jail, but aint no bail".
And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him.
Repent of your sins and believe in Him!.
I'm a civil engineer, and when I used to design shutters to contain wet concrete, for example to form tall narrow walls, the builders on site used to ask me, 'why is the pressure so high? theres only a small amount of concrete going in'. I just used to say thats what the hydrostatic pressure calculations give me, but i couldnt quite answer exactly why. They used to think i was going over the top by putting in reinforced joists on the shutter panels to withstand the forces.
I'm glad I've finally found the answer to this question. I'll send the guys on site the link to this video next time they start questioning my formwork designs.
I used to design instruments for industrial use and there's specifications for water resistance. One was a spray hose but that required an equivalent fire-fighter 2 inch size (to large) or a depth of six feet (a large volume of water). What I used was to take a 50 gal drum 34 inches high, not tll enough. So I put a cover on it and screwed a 3ft 2in pipe in the fill hole and got my 6 feet deep of pressure to test my instrument.
Not sure how you did it, but you just taught me about 5 different things at once. Also, the lecturer is great to watch and listen to. Excellent stuff!
What an elegant, non intimidating demonstration of Pascals laws.
Thank you.
I like that she talks like an adult. Compare to so many other channels where they uptalk and otherwise sounds like a child. This is very refreshing.
I was just looking for the explanation of the sideway tube, and of course, it's the only one you leave out!!!
The explanation is simple. It is a combination of the previous two examples. The upper surface of the slanted tube exerts a downward force that adds weight and the lower surface exerts an upper force that reduces weight. If you apply the virtual volume concept (imagine a fluid mass reaching outside the surface to the level of the fluid) you will realize that the downward force is slightly bigger than the upward one. This is because the upper surface is slightly bigger than the upper ward force which means that an additional weight is applied precisely equal to the weight of the slanted volume of the fluid
Water has a head pressure of about 0.43 PSI per foot of height. So, a 75ft column of water has a head pressure of about 32 PSI. That's about 2 atmospheres.
9:17 You also have to pump 11 times the volume of liquid through your pump. It is very much like lever arms except we are now talking about volume of liquid. The small piston moves 11 inches for every inch the large piston moves.
This exactly. I thought I had forgotten how to math. Great video just wish they had taken more time to explain the math so I could figure out what I was doing wrong or they could see they messed up the math. I was using 14.7 psi for every 33 feet of seawater(.445 PSI/foot but close enough to .43 for fresh water). The one atmosphere of 14.7 PSI would be essentially the same at the top and bottom of tube and all around the vessel so it cancels. I always wonder if I am crazy when someone smarter than me makes an arithmetic error or misplaces a decimal or confuses units. Still occurs to me that we could be completely wrong and missing some subtle aspect of this.
@@mrous1038 Let me teach you an arithmetic trick. You will notice she is dividing 1,250 by 5 to get 250. Division by 5 is the same as multiplying by 2 and dividing by 10. 1/5=2/10 so the trick is this, multiply the number by 2 and move the decimal 1 place to the left (division by 10). in this case 2 x 1,250 = 2,500 move the decimal to get 250.
Once again, great video. You should show how to calculate the pressure from the 150 foot tube filled with water.
The pressure is 1800" w.c.
Which converts to 65 psig eh
As long as you use proper units, it is calculated as d*g*h, where d is the density of the fluid, g is acceleration of gravity, h is the height of the tube. If you use IS units (Meters, seconds, kilograms...) you need no further conversion. Else, you need some conversions.
And tbis is assuming the tube is large enough that capillary force doesn't become significant ( assuming the total volume is fixed at 1 liter, the height and cross sectional area would be inversely proprtiona) . Once the tube is small enough there would be no additional pressure in the flask.
One of the best science videos I've ever seen.. Your examples are great for understanding the concepts of pressure.
Years ago I was introduced to these and many other laws of fluid dynamics and pressure through SCUBA diving. These really come into play when diving deep and become even more complex when diving deep at altitude. All that aside, I love your explanation here and how lead your students from the known to the unknown. Very well done!
Diving deep at altitude? Now that's a topic I've never seen discussed on TH-cam. I've only ever seen divers as folks who go in the ocean, but there are enormous structures built at altitude that would need divers at some point, I think of dams here. Thank you for that. I'm happy you learnt your lessons well enough to still be 'sucking oxygen' after all this time. Long may it be so.
I wonder if incidents of cetaceans stranding themselves is not owing to accidentally exceeding no-decompression bottom time.
I need teachers like you ❤❤❤❤❤❤❤❤❤
This is a great video series to understand the laws of hydrostatics. It was fun to watch and wants me to grab a hose and barrel for further "research" :-). As it's addressed to a broad US audience, I understand the usage of units like psi, lbs and in². Nonetheless it could have been even better if you additionally had added the common SI units for your international audience.
Will do, for future videos!
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you get into hell. It is jail, but aint no bail".
And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him.
Repent of your sins and believe in Him!.
We use FREEDOM UNITS, 'round here!🇺🇸✊🏻🗽🦅
@@neaworld3960 The wages of sin [i.e. death] increase expositionaley, when stacked on top one another! As apposed to the free gift of God's everlasting life! [IF?] you can believe?
@@stevemitz4740 hiii . I do suppose you mean that God cant save, however, He vcreated the universe, (which would not exist without a creator, and the evolutionary theory fails to prove the non existemce of a creator) im sure His Only Son's sacrificial death on a wooden cross where He took the wrath of God for you, because of sin, upon Himself. Do you know how much Jesus loves you? Neither angels, nor darkness can separate you from His bountious love towards you. GOD looks upon you with compassion, and me too, for though we " all have sinned and fallen short of (His Holy standard) the glory of God, God seeks to turn you back to Him. He loves you and created you to be happy, fruitful and joyous in communion with Him. Trust me.. if it were not for the love of God, i would not be telling you these things today, because naturally I am a mean-kinda gal and God Himself has poured His love into my heart. Añl He is asking you to do today is turn from your sin and to Him. He will be right there for you. He will never fail you. I know past relationships have failed you, but " [God] will never leave nor forsake thee". He won't fail, he won't walk out when things get bad, ; He will be there. Amd He has been threre your whole life. You just need to open the door [of your heart] to Him today.
The best way to explain hydrostatic paradox! Even though her way of talking is slow....it gives us time to get the idea into our brain....I appreciate her examples with different shapes of vessels containing same height of liquid...the last one may seem really tricky but if you look close to it...you can figure it out that even though the liquid tis not directly under it's base....as pressure act in every dirction...we can get the vertical liquid column in a zigzag way...thank you so much for uploding such a video...I learnt so many things....keep uploading...wish you the best.
Very clear and lucid but my favorite bit was to introduce me to someone I had never heard of, Simon Stevin. One of those ridiculously brilliant people all the world ought to remember beside Kepler and Galileo.
The best explanation of the Pascal's principle paradox I've ever heard. Thank you a lot Madam.
Wow, I do not say this lightly. This video just blew my mind. How did such basic physics escape me for so long? Excellent video, I am, of course, subscribed with notifications turned on, and thumbs up!
Excellent!!
As far as I know, the hydraulic lift (not the hydraulic jack) used to lift vehicles doesnt utilise the force multiplication effect. The cylinder piston under the vehicle is actually of lower area and is used to move the vehicle up over a longer distance. The larger area cylinder piston is the one where pressure is applied on a barrel of oil using an air compressor. It requires more force, but that is achieved using air. So it works on Pascal's principle, but contrary to what is commonly explained for the hydraulic lift, the car is not lifted by force amplification.
Your examples are great for understanding the concepts of pressure
as a physics teacher, I must say this was truly awesome and inspiring.
Keep up the good work!
Please keep making more videos ❤❤
Absolutely brilliant backed up with some excellent demonstrations. Thanks for taking the time to make this!
loved the way she joked with a serious face......" 2:52 "
Great video, I also really appreciated the addition of biology into a physics video. It really shows that their is connection between the sciences, and it gave a great example of applied physics.
I totally love the reference to animals and the comparison. These days I reckon its pretty critical to help students realise connection to the natural world, rather than just mechanics.
Hey there! Have you heard about sin? Basically, it is anything that is wrong that we do to upset God. Sin upsets God because He is Holy. Just like this( Imagine if you saw someone being robbed!) God does not like sin, and Heaven is His God's home. So imagine you are sinning and trying to enter into God's house! What happens is, you OWN'T end up in God's House! Basically, you end up in Satan's, the creature who is decieving souls into going to his house, hell, which will be his permanent residence in a few years, where he wants to take millions of souls including yours! There is no second chance when you gte into hell. It is jail, but aint no bail".
And that's why Jesus died. He died in our place, that we might just have a chance at life if we believed in Him.
Repent of your sins and believe in Him!.
*_Here the real (math) paradox_* for me at 0:20 => the height of the water in the straw was said to be 75 ft. I was taught that a height of approx 34 ft of water produced 1 bar or (which is the same thing) 1 atmosphere of pressure. So, 75/34 = 2.2 bar = 2.2 atmospheres. Now 1 bar or 1 atmosphere of pressure is approx *_14.7 psi_* . Therefore 2.2 x 14.7 = *_32.4 psi_* ??? How does this pressure become around *_45 psi_* inside the barrel, as stated in this video? [another way of saying it, in order to have 45 psi water pressure, its height must be 45/14.7 x 34 = *_104 ft_* .]
As a free diver, you can really feel hydrostatic pressure once you dive down -30'. I'm not sure if I even hung out at -60' but at the negative 40'-50' range you really feel the hydrostatic pressure in your internals. On the bright side, If you want to look skinny, take a selfie at -60'.
Crystal Clear explanation, while watching the video by itself is very pleasant the way it is made and presented by this lady. One would not expect that a subject like this could be so interesting
I have seen a turbine at a off-grid location that generates electricity powered by hydrostatic pressure. Water is ejected at great pressure from the bottom of a pipe that is laid in a stream bottom with its inlet some elevation above the outlet. The pipe must be made progressively thicker from top to bottom to hold the pressure.
What a great example of how engineers must account for the laws of pressure when designing the power plant. Thanks for sharing!
This video made sense of a phenomena that I've been aware of for quite some years but never actually understood. Thank you for such a succinct and understandable explanation! 👍
I bet it also made sense to the 5 in the experimental deep sea Titan coffin!
Imagine how thick a heart a brontosaurus would have to have had.
a rough size would be about the size of an adult head .... imagine how much force that muscle would be exerting each and every pump
@@kaboom-zf2bl the human heart pumps about 19 kPa of pressure, we can assume if the brontosaurus heart is 2.3 times bigger than a human heart it pumps 2.3 times as much, meaning they pump at about 43.9 kPa of pressure.
@@Doofenshmirtz1088 consider a brontosaurus is 30 feet tall ... we are 6 feet .. so 5 times bigger ... taking the inch and half and increasing it drastically ... a giraffe at 11 feet is at 3inches ....so a 9nch muscle s expected or the size of an adult head at roughly 9inches
That's assuming a brontosaurus regularly held its neck up like a giraffe. If it only did so in short intervals, it could live with less blood pressure because its resting position is lower. Still far greater than a giraffe though!
Search _"How the Brain Limited the Size of Dinosaurs"_ for an article including the parameters of such a heart.
Very clearly narrated and well explained. Thank you for this video and greetings from Scotland.
I am waiting for more videos from this channel.
In so many beautiful ways nature always squares up the books. Work is force over distance. Work expended on the small cylinder in a hydraulic jack has to match the work accomplished at the larger piston.
A small force over a large distance (many repetitions of the jack handle) has to be the same work done at the large cylinder. Because it can't move as far for each cc of fluid, the large piston has to do so with far greater force than the small cylinder.
I deeply regret not paying better attention in school. Physics is wonderful.
Thank you for the food for thought.
Absolutely top class video, please make more!
I have never seen these particular practical experiments, wonderful
So what's the pressure applied to the ground by an elephant in stilettos?
What colour stilettos?
Mrs. Katerina, you are amazing. Thanks a lot for making this video. Indeed it is very informative.
This was so well done I think I understand now. Thank you so much :D
Thanks very much. This was astonishing! You explained difficult concepts very clearly. Indeed, your are a super teacher!
Keep on doing this!
Good. It cleared all my doubts.
Such a perspicuously elucidated and well laid out video. Hoping you'll post more of these:)
Dr. Visnjic:
Thank you. Great video fun and great learning I thought I knew, and very well presented. That was nice to give credit to Mr. Stevin.
I had some minor notes/questions, sincere apologies if they are obvious or wrong. Pls forgive the numbering, its just for me to attempt being organized!
1. The point about all points in a fluid being at same pressure isn't quite right, is it, under gravity, since the fluid has mass, if the vessel is not all at one height, isnt that correct.
2. The pressure in the vessel also wouldnt be equal everywhere, if the fluid were moving, say if the fluid was rotating in the vessel, or convecting. or vessel is in noninertial frame?
3a.. It would be great to understand the role of atmospheric pressure here, especially if it were low, say down here vapor pressure; and if gravity were much higher;
3b. and how the results would be different if the vessels tops were not open to the air.
3c. and Especially,, with the cool barrel experiment, what if the top of the 150 ft tube was sealed, before pressure applied at the barrel. what would happen, at that height,150? feet? I guess all the gases would come out of solution at the top; then the fluid water at top would starts to vaporize in near vacuum.and the plastic tube would shrinks everywhere, and the barrel still explodes?
4. And if I had a wishlist, I would love to understand the relation of static pressures, such as shown shown here, to the vessels' "capacities, like a battery, and the output Impedances" or what an EE like me would call it, (dynamic heads?)say of the different shapes as here and the same initial flluid height height, for instance the martini 630g glass vessel I would say has high capacity, initially at least, and llow output impedance to flow out of its bottom aperture, while the one with the thin top, would have low capacity and high output impedance to flow out of it's bottom aperture?
Thanks for your work and cool demos, and any consideration,
Best regards,
this is an extremly amazing video. i´ve had very good physics teachers throughout my life but this is top level even amongst them. keep doing those videos.
You have some of the most intuitive explanations on the net. Thank you and keep up the great work.
Still Gisele. I have my reasons
Best explanation of hydrostatic paradox I had ever come across!
Thank you for the amazing video. Just one question about the third container, we knew intuitively that the water will seep out and your explanation was based on this statement. If there was no column of water above the container the water would not have seeped out, could you please give a more detailed explanation on how is the pressure transmitteted from the vertical column of water to the rest of the container?
very good communication skills good explicit explaination very informative video.
Giselle ...the answer is definitely Giselle!
I had this principle become important when using a direct reading pressure gauge to measure oil pressure of a very large helicopter (CH53E) transmission. The gauge was on a long hose which could be moved about 6 feet below the bottom of the transmission. The pressure increased a few ( 1 or 2) psi when the gauge was moved to the floor of the helicopter.
That’s intriguing to know. Does that cable move like that when in flight?
@@Anksh0usRacing No. The cable or more correctly the hose and direct reading pressure gauge are not part of the aircraft. The normal pressure sensing device is a pressure switch mounted on the transmission. We were using the direct reading gauge as part of a test.
It's 2,81 kg/cm^2 :D You're welcome.
You: 1:06 "made the mistake of writing in Dutch not in the scientific language of Latin"
Me: "made the mistake of using imperial units instead using the scientific SI units" :D
1 mile = 1760 yards
1 km = 1000 meters
Correct me if I'm wrong.
Nevertheless it's a GREAT video.
OMG, best comment ever ;) I'm totally with you. It's not like imperial is bad and the end it's just a set of units and numbers that you learn as the kid and got used to it. What is bad is inconsistency that it produces. For example all electric and magnetic laws are based on SI International Measurement System with uses metric units (kilograms, meters). Volt is at the end (kg*m^2)/(A*s^3), ohm is at the end (kg*m^2)/(s^3*A^2). Not using metric system which is International Standard or using Imperial units mixed with metric (like wire resistance Ohm per feet, blaaahh) is a tumor on measurement consistency.
Thanks professor Katrina, I never seen such beautiful professor giving very simple yet clear explanation. I wish we could have applied real time calculations as well.
@Physics4Life this video is awesome! I learned a lot. One thing I would appreciate though is if you could give a brief answer/explanation to your question about the slanted water tube mentioned at 7:48 of the video either in the description or here please.
I think it is because as the water is pushing against the walls of the slanted tube the vertical component of the pushing force increases the weight on top of the balance and so we need 50g weight to balance it even though most of the water is away from the stopper
Just an assumption tho😕
@@summerr0503 do you think that would happen in all tube like containers? Like if you had a silly straw like shape? Would the pressure only accumulate on the vertical axis of the water? And would the walls contain the weight like those in the examples?
@@alanbaraka9800 For tube of any shape the weighing machine will measure the weight acting directly on it, as for the pressure in any weird shaped tube need not be acting perpendicularly over the machine(as in the third case) so the weighing machine only measures the force generated by the vertical component of pressure exerted by the water, but the entire weight of water is indeed supported by the walls of the tube
@@summerr0503 interesting
Slanted water filled upto same vertical height will also lift only 50gm.
This is because..
Lifting up force by the lower surface of slanted glass is cancelling some of the pushing down force by the upper surface of slanted glass.
Excellent video, definitely adding to my homeschool playlist.
for the slanted one, one of the sides exerts a reaction force down while the other up so the pressure would just be the same as the others at the same height?
seriously it is one of the best science videos I've ever seen.
Varun Pathak Sir's Students
Physics made easy and fun.
I wish my teacher was able to explain physic phenomena this easy, interesting, and fun.
I was shopping when another customer asked for a suction pump that was supposed to suck water up 12 meters.
The clerk told him that such pumps don't exist. The customer was stressed and visibly disappointed and began protesting this. Then I said the clerk was right. Such pumps doesn't exist and are impossible to made.
The customer was even more stressed. Nobody said a word for at least half a minute. Then the clerk said to the customer that he could buy a pump that could _pump_ water up 12 meters.
Physics is just fun!
776 views?!? this video is legit! You'll be eating a million views for breakfast if you keep it up!
Yeah ! 😂,the Quality Of The Video Is On Point Too !
Wonderful content and beautiful and historic demonstrations. Beautifully presented.
As a geologist I learned that (fresh) water exerts a pressure of 0.433 pounds per square inch per foot. Therefore a tube 100 feet high would exert a pressure of 43.3 psi at its base, regardless of the diameter of the tube. This was critically important in assessing the weight of fluids needed to withhold fluid influxes in a borehole.
ya I really hate it when someone gets it all so wrong, but hay kept the kids quiet, and looked good. I had to thumbs down as soon as she said 75 ft head of water was 45 psi ???????WHAT
Stimulatingly delightful video. Relearned, with better clarity, few 101 concepts, grateful for that. Appreciate the effort that went into its making, by the Professor and the entire team.
Forgive my pedantic quibble though; it took me some time to understand the weighing set-up. Dunces like me could benefit had the stopper and lower tube coupling been further elaborated.
Save for this petty nitpick, the video undoubtedly is purely edifying.
An application that comes to my mind is the use of surge tanks to relieve immediate pressure surges, like due to the closing of valves, somewhere in the pipping system, which by Pascal's law will be equally transmitted throughout the system.
what is the answer to the question?????
Yeah! second this. I can understand the pressure in the other containers but the angled column seems as if it would be reacted against by the glass and not the lower plate, however this is not the case
@@sluggi95 If we try this experiment with manometer then there will be any difference in manomatric fluid??
Excellent explanations and descriptive analogies. Well done!
Nice video but that imperial system gave me cancer
dumbass
Hooollyyy this deserves more views!! Algorithm pls boost! This is by far one of the best academic-education videos I've seen. I've long believed that it's the practical demonstrations most students need in order to truly appreciate the sciences. Thank you
very good video!
spanish subs please!!
i just discover this chanel , very clear and simply explained ! good work
This is the best explanation of this topic. Cleared each doubt completely.
I'm not sure how I ended up at this video, but I'm glad I saw it. Very interesting and well-presented.
Nice work. Clear about facts and well presented
Air is also a fluid and consequently follows these laws too. When we examine the water or air-flow through a propellor we find that there is a reduced pressure ahead of the propeller and an increased pressure behind it. This provides the generated thrust but the kinetic energy in the accelerated flow behind the propellor is wasted and the propulsive efficiency of a propellor would be greater if the flattish disk (or actuator-disc) of rotation of its blades could be replaced with something else. Were a centrifugal fan used instead of an actuator disc, to accelerate the water or air-speed and then the resulting radial flow turned to pass behind and parallel to the axis of this fan's rotation, this loss in propulsive efficiency would be partly avoided.
This channel deserves atleast 10M subs
That video on the giraffe will explain the pressure regulating mechanism that prevents the giraffe's head from exploding when it lowers it below the heart to drink. Fascinating stuff.
I just really impressed that you got a water tight seal between the glass tubing and the scale top
i've paused the radio program on Pascal i'm listening to, to see if some of his stuff was here on TH-cam.. i'm looking forward to getting back to the program but so pleased and grateful for this..
thankyou for sharing 🙂 x
Literally this video saved me, in our textbook they have explained this concept in a grand total of 1 sentence
What an excellent science video! And what a clear narrator!
Keep these coming!!!! You're a great presenter and speaker, Katrina!
In 1977 at Colorado College i was lucky to take a physics demonstration class by visiting Prof. Julius Sumner Miller, Disney's Physicist. For 2 hours a morning for 3 weeks he did demonstrations and we had to write a notebook with our explanations. It was an amazing class. Dr. Brown from Back to the Future wasn't near as crazy as JSM!
Simple, direct, perfect. Congrats for this beuatiful video
Crystal clear and concise. Very well done.
Ms. Visnjic, thank you for sharing this video, which answered a question I had about aerostatics. I'm looking forward to using the principle and learning more.
A brilliant and very well presented explanation. Where were these when we needed them in school physics classes. Keep them coming 👍🙂
You gave me the whole answer for my research of an week. Thank you and thank you again...
Plsssss dont stop making videoes .....you really help hs ❤
she has to have amazing explanations, as the students can't stop staring at her ;-) beautiful presentation, thanks
Finally, a great explanation on this topic!
Hope you continue doing videos in the future.
Thank you, you made this topic much easier to understand.
Here is a thought: Fluids are typically thought of as incompressible, but that isn't really true. Fluids do compress under pressure, although much, much less than gasses do. Still, if you pour water into a full barrel through a tall skinny tube, a little bit of that water will actually be forced into the barrel by the pressure of the water above it. And even though the amount is small, because water is almost incompressible adding a small amount of water to an already full barrel will increase the pressure enormously.
For me this explains why the width of the tube doesn't matter. The barrel breaks when a sufficient volume of additional water has been forced into it, and you can eventually add any amount of water through a tube of any width. If you are using a needle thin tube, the level of the water at the top of tube will drop as a tiny amount of water from the bottom gets forced into the barrel. This probably won't be enough to break the barrel, so you will probably need to top off the tube repeatedly. But eventually, even through a needle thin tube, you will have forced enough additional water into the barrel to break it. I find this a very satisfying explanation -- what do you think?
Seeing no one responded to your question, I will. First, your statement that adding a small amount of water to an already full barrel will increase the pressure enormously is a bit ambiguous so my interpretation of the statement is unsure. And a needle-thin tube I think would be too thin to work. To try to understand the behavior based on the accepted hydrostatic principle, that the pressure / force exerted by the liquid against the container walls is based on the hydrostatic pressure rather than liquid's mass, is wrong; the pressure / force exerted is actually based on the liquid's mass which is very easy to prove both with mechanics and experimentally.
this was soooooo cool, you explained it so well that i understood something that i have been ponderin (just in my head from time to time) about from time to time ever since i know about myself