Absolutely true John, but it is an interesting bit of physics where the fluid flows up hill first without any obvious pump or source of energy! There is still some debate in the physics community about the exact mechanism and if it is the same in all cases. All good fun!
@@AnthonyFrancisJones What you have to look at is the elevation of the input and output, the hose looping up or down is irrelevant. Just make sure there are no bubbles in the hose, and the side that's lower will pull it.
@JohnSmith-ii8pp does the loop effect the speed at wich it happends? For example if the loop goes up 4meters before going down would the speed at wich it happends be greater than a loop that only goes up 1meter. Given that the Intake and outake of each loop didnt change
@@AnthonyFrancisJonesdoes the loop effect the speed at wich it happends? For example if the loop goes up 4meters before going down would the speed at wich it happends be greater than a loop that only goes up 1meter. Given that the Intake and outake of each loop didnt change
thankyou for telling us that they are not sure on the reason this works i have been trying to find the reason or what forces are working on the liquid to make this happen.
I think there are those that post 'definitive' answers out there but I think the general consensus is that the effect is still not fully understood. Glad it helped and thanks for watching!
my question would be could you siphon back to the glass using more hose in the upper glass? maybe coiling the hose to creating the pressure needed to pull the fluid up hill until the water levels are equal????
Sadly without another source of energy (pump) this is not possible. There is a 'cheat' where you seal the pipe into the upper glass and have a lower pressure in it (close to a vacuum) - then the atmosphere will do the work. Have a look at my 'Tea on Everest' for a demo of this one! ua-cam.com/video/wIEsDY-EieE/v-deo.html Thanks for your question. Always good to think about physics!
Thanks Brian, that's really kind of you. So glad you liked the video. Not an easy one to explain - if I ever did! Thanks for taking the time to comment and making it all worthwhile!
surely its due to moleculuar dipoles interacting with each other and the negative pressure we induce into the system flows like a waveform through the dipole lattice?
Thanks, yes intermolecular forces have to be important here. Not sure what you mean by 'negative' pressure but I guess you are referring to gauge pressure. Discussing pressure on an individual molecular level is not an easy one either! Thanks for watching and taking the time to comment.
@@AnthonyFrancisJones hiya dude, i should have said, that when the vaccuum is pulled there is a change in pressure (being less than 1atm its refered to as negative, gauge pressure is positive pressure or higher than 1atm. Because the glass containing the orange juice is open to atmospheric pressure (a constant force) we can pull vaccum, if it were air tight sealed we could use gauge pressure (blow) to displace the liquid, interestingly the higher density of liquid is acting like a gas seal, but its not so dense that its immovable and because liquids can flow, it works! as a side note, Roley Moley was the undisputed king of fuel running in my home town, selling 25 litres of diesel for £15 to other main car dealerships! he would sipphon trucks, plant machinery anything, he claimed to have procured over 800 litres one night hand lugging the produce over a mile. (800/50 =16 miles with 25kg on each arm!) he was an addict but thankfully Roley Moley is rehabilitated and living life as a good family man, he got his nickname by rolling a customers car just after it had been resprayed 😂 i wanted to do a vice style documentary with him but he declined for political reasons...
Good question. No, the inlet and level always has to be above the outlet level. The system is trying to minimise gravitational potential energy so unfortunately this is not possible. If you got it started and cut the tube at the high point it would just all flow back down the tube and stop working too.
@@AnthonyFrancisJones is there any method to transfer liquid to a higher point without electrical power via an electric pump. For example, getting water from a sump tank back into a fish tank?
@@solarjudgement4575 Another good question. I think in the situation you are thinking off the answer is no. Now, just for interests sake, very slow processes like capillary action would work ua-cam.com/video/s2VNbrfM01k/v-deo.html or situations like evaporation and condensation, where water slowly evaporates and then condenses on a higher cold surface and drips off. There are interesting technical solutions for a bigger scale such as the ram pump. But, the main thing is there has to be a source of energy for all these processes to work.
Love the video, thanks. Can you answer this for me please. I am trying to gravity feed my tomato plants using a high position reservoir via a small-bore clear tube & variable flow tap. Whilst I can set it to flow slowly it refuses to set to a slow drip & simply creates intermittent air voids throughout the clear tubing. Having successfully set it to a slow drip it then stops. Any clues please? Thanks.
Thanks and glad you liked the video. So it could be a number of things. The bore of the tube is too narrow (or in some situations but probably not yours too wide). Also not enough head so the feed tank needs to be higher. But, I suspect the tap! It needs to be very narrow diameter in its output end. Have a look at a lab burette (I think they are available in plastic too rather than glass) and you will see what I mean - they are designed to drip or offer very low flow rates. Let me know how you get on!
your explanation looks correct, gravity pulls the liquid, and low pressure inside the tube does the rest, just like when a syringe pulls liquid from a bottle, even if it's against gravity
Thanks - the issue you have to grapple with though is why gravity does not do its bit on both sides! Something to ponder. If you want another thing to think about with a syringe the lower pressure is inside the syringe as you say but with a syphon the lower (atmospheric) pressure on the surface of the liquid is actually on the higher container! Isn't physics great!
Good question, yes it would keep going for as long as the level of the upper tank hose opening is above the level of the lower end opening. You don't want to block the lower opening with liquid but let it flow freely into the air. Hope that helps.
So does this mean that I didn't actually have to buy a water transfer pump to move water from one barrel on one side of my house to another on the far side? I just need a long enough hose?
Yes, sure but remember it is all about the level difference and of course the point of this video is showing the water/orange go up hill first and then further down. You would of course not normally do that for a permanent installation as you could have a hole in the bottom of the higher container with a hose to the lower one. The beauty of the syphon, and perhaps I did not make this fully clear in the video is that it works when you only have access to the TOP of the upper container such as when I was syphoning the tractor petrol AND you do not have a pump. Hope that all makes sense! Thanks for watching.
@@AnthonyFrancisJones No, your demonstration perfectly illustrated the process 👌🏻 Basically, at my mom's, there are 2 rain barrels at opposite sides on the property, but only one collects water from the rain gutters, so when that one gets full, I transfer its contents into the empty one at the opposite end. I've been doing it via hoses and a small portable plug-in transfer pump, but if there were a way to achieve the same outcome without the noise and hassle of setting that all up every time, that'd be great!
Sounds like a syphon would work. Remember the outlet pipe needs to be lower than the inlet end and the inlet end must always be in water otherwise you will have to restart the syphon. So if the rain is not coming in as fast as you are taking it out this will happen!
Good question. No, unfortunately with the same apparatus you cannot. There would have to be a source of energy for the liquid to gain the extra gravitational potential energy to end up higher. Hope that helps and thanks for your question.
Hi profesor. I've been trying to understand this problem for days. I've come a long way, and from what I've gathered, most of the scientific consensus seems to flow towards explaining this behaviour kinda the same way you did. And even though when I first heard it I went "aha!", there is something that I just can't get my head arround. If the thing which is driving the siphon it's this two facts: *The outward tube side colummn of liquid falls because of gravity *The rest of the liquid either follows it through water cohesion or through little vacuums created and pressure differences. If those two statements are correct. Then Why does the exit of the tube NEEDS to be at a lower level than the reservoir liquid surface? Doesn't those two conditions apply at any point in the tube where the liquid is falling?
Federico, good question. So one way to think about it is that the liquid in the output pipe is a longer column length so has a greater weight than that in the upwards liquid flow pipe. Some people think of the highest point of the tube as a pulley and the liquid as rope with a weight at either end hanging over the pulley. The weight on the heavier side will fall and the other side will rise. Not a great 'explanation' but hope that helps a bit if you think of the liquid as having cohesive forces throughout it (such as hydrogen bonds).
@@AnthonyFrancisJones oh! Then if the chain is lighter on the outward side of the tube, then the whole system Will just fall back to the reservoir, right? Is a good analogy, it does give me some sort of ease of mind. Thanks for answering my question proffesor! Greetings from Argentina!
@@federicouliseslopez406 Yes, that is right, so the output tube and column has to be longer below the highest point in the tube, in other words below the input side.
Robert - that is a really good question. Not sure the density would make much of a difference as the liquid has to be lifted before it falls as it were (though I am going to have to think a bit harder about this...) I guess the real difference would be with different viscosities where gasoline should be the fastest flow rate. Very interesting question. Thanks for taking the time to watch and comment.
@@AnthonyFrancisJones my thought process was more density would mean more mass more mass would mean the effect of gravity would be stronger. Viscosity certainly would play a roll, yes.
@@robertcampomizzi7988 Yes, though remember you have to lift the extra mass against gravity in the first place. The distance between the liquid surface and the exit of the pipe vertically makes a difference until it is limited by viscous friction with the side walls of the tube. As with everything in physics, there is more going on here than my rather simple demo as you have pointed out!
I just carried this experiment out and found that the only way to reverse gravitational effect is by using forced energy,, This begs the question if its possible to create this forced energy by some way or means to incerting a propeller unit so when water is syphoned at the syphoning point the draw creates the energy internally to drive the flow faster and by switching the propeller in the opossit direction of rotation so drives the fluid flow up hill i assume this unit can be made fitted nano tech, Its worth testing,, I assume suction can drove a propeller by forcevof gravity which in turn would be the driving force behind the flow,,a nano built in system that allowed to defy gravitational force by margin,,i wont claim it will full be 100℅ But would go some way to defining an equivocal and concise answer.
Good question. As ever the Law of Conservation of Energy, and thermodynamics laws/entropy are against us here so, as no system can be 100% efficient we would need to add some energy to the system to get the water to go back up from an external source. The skill is to make the external source look as 'invisible' as possible!
Yes, possibly but really it is more a case of capillary action as the water mainly only goes upward. There is also the effect of water then evaporating away from the surface of the leaves. But, there are no pumps in a plant - just good old capillary action! The joy of physics, as you have noticed is you can use it in all sorts of different situations to explain what is happening. I have done a video on capillary action too that you might enjoy. Regardless, thanks for watching!
I would say its just a vacuum effect. The liquid is creating a vacuum. It seems pretty simple really. Also gravity playing ita part. Think of it like a train going over a hill. If you have enough weight on the down grade it can pull the other part up with no outside force at all. With the liquid the pull of the liquid going down is stronger that the other liquid coming up. So maybe with a long enough hose and syphoning it up to the end you could make it pull uphill a bit. But your downhill would need to be longer into you higher glass. Would be tricky if possible.
Thanks for that. Yes, your train model is a good one as the train carriages are coupled as are the water molecules with intermolecular forces. There may be a lower pressure but not a vacuum as the liquid would immediately vaporise - you might have seen my Tea on Everest video - ua-cam.com/video/wIEsDY-EieE/v-deo.html In terms of finally flowing up hill - this is not possible with one exception, if the liquid already has some kinetic energy imparted to it. A bit like walking with a cup of tea and shaking it - the tea will go up hill over the cup walls. Thanks so much for watching and taking the time to comment. It is really good science to discuss things and how they work whether one agrees or not. Hope you enjoy the other videos too!
Many call it suction but really what you are looking at is a reduction of pressure compared to another place. I try to explain to pupils that 'vacuums do not suck' what happens is the higher pressure (and therefore moving particles) rush in. Really they have a higher mean free path in the direction of the low pressure but the vacuum does not magically draw (suck) them in!
Hello.. I want to ask.. Can the water increase its pressure when u make an tube arc that ishigher. Imagine when 3 floors. 1st floor is the the outlet. 2nd floor is the water jug(source of water) And 3rd is the water arc of the water pipe We all know that we can directly get water from the source in the 2nd floor directly to the 1st floor.. The question is.. If we increase the height of the tupe upto the 3rd floor. It will increase?
Brilliant question! So, in pure syphoning the water flow is affected by the vertical height difference of the top water surface and the exit on the lower hose. So, raising the top of the loop higher but keeping the other positions the same will make no difference as long as the syphon is working. It's a really fantastic question you have asked and I really should demonstrate it at some stage. Thanks for taking the time to comment and keep thinking like this - that's what good science is all about!
Yes, good point. The tube we used was very narrow and by the time I had decanted some and then poured it into the tube it would probably be all over the place! To be honest, you get quite good at it and even if there is a bit of air left at the end that you suck, as long as you seal it briefly and then lower that end quickly it all works fine, without getting a mouthful!
I did Production Engineering - then a post grad in physics education at Cambridge, which was outstanding. I was also brilliantly taught at school - the rest speaks for itself Kerem. I of course started early as a child with brilliant support from my parents. I think my dad bought me an oscilloscope when I was 14!
@@AnthonyFrancisJones thanks for the explanation I am considering between mechanical engineering and electrical engineering. What would you say for a person who loves physics and would love to be able to build machines and robotics. Which branch would be better or can you share your knowledge about those practices
@@keremalp4627 Both are equally useful - best idea is to ask very careful about the courses before you choose. There are so many different engineering disciplines too so check all that are available to you. Two other thoughts - study one and specialise later. Also in the UK there are courses especially for robotics. Personally I am a great fun of 'get the basics and specialise later'. Hope that helps a bit! Most of all, and this is really important, do what you enjoy and the rest will come.
Good question. Basically no unless there is a pressure difference that allows for it to happen but that would not be syphoning! Perhaps I should have lifted the output hose end to show where it would fail to work - above the inlet. To do what you ask it would have to gain gravitational potential energy from somewhere so something would have to allow that to happen and if it did it is not a simple syphon system but something more complex with another source of energy. Thanks for the question and glad the video got you thinking!
Thanks for your question Frank - you are thinking of something else - have a look at my video on Pascal's Law and I hope that explains it! ua-cam.com/video/PE5PV3F1-6w/v-deo.html
Yes, I take your point - it is only flowing up hill for some of the path it takes. Now capillary action is a completely different matter so you might enjoy this... ua-cam.com/video/s2VNbrfM01k/v-deo.html
Thanks Michael. I am sorry (for myself) as I am unable to claim a coffee at your expense (kind offer) as there is no way the laws of physics allow for this to happen unless there is an external source of energy. If it comes from the system itself there will always be losses (friction is a good place to start) so it can never work in that way. Shame, but physics does not allow us to share a coffee together!
This might sound crazy but i got thinking,,could it be possible with a hosepipe that a Nano apparatouse of some description like maybe a Nano rotary pump,or Nano propeller using force of gravity to drive the flow on and,above,, Okay its clear a syphon,syphones from one bowle to another but lets say it was possible to create an aparatouse that could be connected onto or into a hose that would function from the waterfirce of gravitational effect to drive the flow up and beyond lets say? 6ft which in effect by all standards of a new developed product that would create new products, I found on a simple test when you squease water in a soft object it creates force,,so i wondered wether that such force could be captured on routevto its host,,thus the gravitational effect with that force to so drive to a,set point,,,without the need for applying battery,electric or a fuel driven device,,only by gravitation and such a device that captures and pushes on that force isolating out a Ram Pump,,etc.
Yes, an external force (that moves) would help. Such as squeezing the hose with a valve in it to stop return (I am working on a Tesla Valve video at the moment). A ram pump is a brilliant device but still needs an external source of energy.
Orange juice is acidic and the top glass is on top metal can be charged with electrical force but now with ether and solenoid can transfer without pipe and that is how lower price of gasoline but what if it can be stolen ...that is why German engineering use diesel which is harder to stole than gasoline or air plane jet fuel
It is an odd effect! Works perfectly well with water but I used orange juice so you could see it better on the video. Main thing is that the hose is completely full and that the container the outlet of the pipe must be lower than the inlet so overall the mass of the liquid falls. Thanks for watching!
Will the liquid climb up against gravity if we create a vacuum in empty cup (the higher one), I'ven't experimented it myself but I guess if the vacuum is strong enough it would pull the liquid back till the pressure become steady, right?
Good question Hamed - Yes the water would go up to the container with the vacuum - remember the vacuum does not pull the water up - the atmosphere pushes it in! There are also issues with it causing the water to boil (at room temperature too!) You will see me do this in this video - it is quite fun! Hope you enjoy it! ua-cam.com/video/wIEsDY-EieE/v-deo.html
It happens because liquid will always follow the lowest part regardless of whether it needs to go up before going down. As long as the end of the flow is lower than the beginning. Everyone who has a rain catchment system that is then gravity fed on their homestead knows this.
Yes, indeed and that is a good application if there is a syphoning part but we need to explain 'why' liquids do this rather that they 'do' do this and that is not so easy, nor are all scientists in agreement about the cause of the process of syphoning. Such are the joys of science!
Sorry about that Joshua! The liquid does indeed go uphill without any 'obvious' source of additional gravitational potential energy but in the end the output must be lower. It is still very counterintuitive!
Good question! Not really I am afraid without an external source of energy. Now capillary action is a different matter - Here is a link to my video on that. ua-cam.com/video/s2VNbrfM01k/v-deo.html
Yes, that's interesting - I know that when a reasonably large bubble gets in the syphon fails. Gases can change their volume quite easily so this may be part of it as well as there being no cohesion forces between the molecules as they are about 2000 times further apart. I can visualise the kind of apparatus you are thinking of - if only I had more time! Great idea and thanks for taking the time to comment.
@@AnthonyFrancisJones What you are asking about is called a "water elevator". It uses are to move the water up. Look for it on YT. Also look up videos on trompe. Bell siphons also. The tromp makes air pressure. The Bell siphon helps to empty your tank automatically. You use the air pressure from the trunk to make the bubbles for your water elevator. Blessings on your much success amen.
Krishansh, I am not quite sure what you are asking but it would not syphon to the upper container. However, liquids can flow uphill without going back down if that is what you mean - you need much smaller 'pipes' so have a look at my video on Capillary Action. Thanks for your question. ua-cam.com/video/s2VNbrfM01k/v-deo.html
That would be a challenge! I guess a pump is the order of the day but you might be interested in the Mould Effect or Chain Fountain as it is sometimes known.
@@AnthonyFrancisJones Please do some videos on the Trompe that was invented in the 1600s to create pressurized air to run forges and air pressure equipment. Then with all the pressurized air you can move the water uphill with a device called a water elevator that pushes air up through a pipe filled with water and gets the water to go up. All of it really interesting stuff and you would be great at showing it to your UA-cam fans. Many blessings in your endeavors and success amen.
@@reypolice5231 Thanks for the suggestion - it is a very interesting device. I remember my father teaching me when I was little about the Ram Pump and saying how amazing it was as it seemed to work as if by magic but of course underlying good science! You are right - it is amazing how ancient these devices are. As an aside I have Hero's Engine on my long list of films to make too!
That's not an uphill siphon! That's just a normal siphon... Because the end of the pipe is lower than the other... Uphill siphon should be the opposite.
Yes, you are of course right - the interesting bit is why the fluid flows up in the first place without an apparent source of energy - of course there is but it is not very obvious such as having a pump or similar. Still a very interesting effect that is misunderstood by many. Thanks for watching!
Sorry about that. I have had a listen through again and don't seem to hear what you refer too. I know my large lab has quite an echo and it was filmed during the working day in a school. I now film with a tie clip mic which helps. Any further suggestions greatly received.
This is just what I needed thank you if I were your dad I probably would’ve just build a bridge and on top Then you could pour iteasily or make a regular siphon easily
Hope you enjoy the videos! Please consider supporting my work by buying me a coffee at
www.buymeacoffee.com/francisjonesa
Very many thanks, F-J
That's called downhill! You have the filled glass at a higher level.
Absolutely true John, but it is an interesting bit of physics where the fluid flows up hill first without any obvious pump or source of energy! There is still some debate in the physics community about the exact mechanism and if it is the same in all cases. All good fun!
@@AnthonyFrancisJones What you have to look at is the elevation of the input and output, the hose looping up or down is irrelevant. Just make sure there are no bubbles in the hose, and the side that's lower will pull it.
Yes that's it!
@JohnSmith-ii8pp does the loop effect the speed at wich it happends? For example if the loop goes up 4meters before going down would the speed at wich it happends be greater than a loop that only goes up 1meter. Given that the Intake and outake of each loop didnt change
@@AnthonyFrancisJonesdoes the loop effect the speed at wich it happends? For example if the loop goes up 4meters before going down would the speed at wich it happends be greater than a loop that only goes up 1meter. Given that the Intake and outake of each loop didnt change
thankyou for telling us that they are not sure on the reason this works i have been trying to find the reason or what forces are working on the liquid to make this happen.
I think there are those that post 'definitive' answers out there but I think the general consensus is that the effect is still not fully understood. Glad it helped and thanks for watching!
my question would be could you siphon back to the glass using more hose in the upper glass? maybe coiling the hose to creating the pressure needed to pull the fluid up hill until the water levels are equal????
Sadly without another source of energy (pump) this is not possible. There is a 'cheat' where you seal the pipe into the upper glass and have a lower pressure in it (close to a vacuum) - then the atmosphere will do the work. Have a look at my 'Tea on Everest' for a demo of this one! ua-cam.com/video/wIEsDY-EieE/v-deo.html Thanks for your question. Always good to think about physics!
What if is in the same level
Love your videos and stories! Great content and super helpful! The demonstration is one of the better on all of UA-cam.
Thanks Brian, that's really kind of you. So glad you liked the video. Not an easy one to explain - if I ever did! Thanks for taking the time to comment and making it all worthwhile!
surely its due to moleculuar dipoles interacting with each other and the negative pressure we induce into the system flows like a waveform through the dipole lattice?
Thanks, yes intermolecular forces have to be important here. Not sure what you mean by 'negative' pressure but I guess you are referring to gauge pressure. Discussing pressure on an individual molecular level is not an easy one either! Thanks for watching and taking the time to comment.
@@AnthonyFrancisJones hiya dude, i should have said, that when the vaccuum is pulled there is a change in pressure (being less than 1atm its refered to as negative, gauge pressure is positive pressure or higher than 1atm.
Because the glass containing the orange juice is open to atmospheric pressure (a constant force) we can pull vaccum, if it were air tight sealed we could use gauge pressure (blow) to displace the liquid, interestingly the higher density of liquid is acting like a gas seal, but its not so dense that its immovable and because liquids can flow, it works!
as a side note, Roley Moley was the undisputed king of fuel running in my home town, selling 25 litres of diesel for £15 to other main car dealerships! he would sipphon trucks, plant machinery anything, he claimed to have procured over 800 litres one night hand lugging the produce over a mile. (800/50 =16 miles with 25kg on each arm!) he was an addict but thankfully Roley Moley is rehabilitated and living life as a good family man, he got his nickname by rolling a customers car just after it had been resprayed 😂
i wanted to do a vice style documentary with him but he declined for political reasons...
Can you siphon the juice back into the higher cup from the lower cup?
Good question. No, the inlet and level always has to be above the outlet level. The system is trying to minimise gravitational potential energy so unfortunately this is not possible. If you got it started and cut the tube at the high point it would just all flow back down the tube and stop working too.
@@AnthonyFrancisJones is there any method to transfer liquid to a higher point without electrical power via an electric pump. For example, getting water from a sump tank back into a fish tank?
@@solarjudgement4575 Another good question. I think in the situation you are thinking off the answer is no. Now, just for interests sake, very slow processes like capillary action would work ua-cam.com/video/s2VNbrfM01k/v-deo.html or situations like evaporation and condensation, where water slowly evaporates and then condenses on a higher cold surface and drips off. There are interesting technical solutions for a bigger scale such as the ram pump. But, the main thing is there has to be a source of energy for all these processes to work.
Love the video, thanks. Can you answer this for me please. I am trying to gravity feed my tomato plants using a high position reservoir via a small-bore clear tube & variable flow tap. Whilst I can set it to flow slowly it refuses to set to a slow drip & simply creates intermittent air voids throughout the clear tubing. Having successfully set it to a slow drip it then stops.
Any clues please? Thanks.
Thanks and glad you liked the video. So it could be a number of things. The bore of the tube is too narrow (or in some situations but probably not yours too wide). Also not enough head so the feed tank needs to be higher. But, I suspect the tap! It needs to be very narrow diameter in its output end. Have a look at a lab burette (I think they are available in plastic too rather than glass) and you will see what I mean - they are designed to drip or offer very low flow rates. Let me know how you get on!
your explanation looks correct, gravity pulls the liquid, and low pressure inside the tube does the rest,
just like when a syringe pulls liquid from a bottle, even if it's against gravity
Thanks - the issue you have to grapple with though is why gravity does not do its bit on both sides! Something to ponder. If you want another thing to think about with a syringe the lower pressure is inside the syringe as you say but with a syphon the lower (atmospheric) pressure on the surface of the liquid is actually on the higher container! Isn't physics great!
If I constantly added liquid to the bottom would it keep going
Good question, yes it would keep going for as long as the level of the upper tank hose opening is above the level of the lower end opening. You don't want to block the lower opening with liquid but let it flow freely into the air. Hope that helps.
So does this mean that I didn't actually have to buy a water transfer pump to move water from one barrel on one side of my house to another on the far side? I just need a long enough hose?
Yes, sure but remember it is all about the level difference and of course the point of this video is showing the water/orange go up hill first and then further down. You would of course not normally do that for a permanent installation as you could have a hole in the bottom of the higher container with a hose to the lower one. The beauty of the syphon, and perhaps I did not make this fully clear in the video is that it works when you only have access to the TOP of the upper container such as when I was syphoning the tractor petrol AND you do not have a pump. Hope that all makes sense! Thanks for watching.
@@AnthonyFrancisJones No, your demonstration perfectly illustrated the process 👌🏻 Basically, at my mom's, there are 2 rain barrels at opposite sides on the property, but only one collects water from the rain gutters, so when that one gets full, I transfer its contents into the empty one at the opposite end. I've been doing it via hoses and a small portable plug-in transfer pump, but if there were a way to achieve the same outcome without the noise and hassle of setting that all up every time, that'd be great!
Sounds like a syphon would work. Remember the outlet pipe needs to be lower than the inlet end and the inlet end must always be in water otherwise you will have to restart the syphon. So if the rain is not coming in as fast as you are taking it out this will happen!
can you get the orange juice back into the elevated cup with the same method?
Good question. No, unfortunately with the same apparatus you cannot. There would have to be a source of energy for the liquid to gain the extra gravitational potential energy to end up higher. Hope that helps and thanks for your question.
Would be an excellent way to drain your water heater if the drain is blocked.
Good idea! It is such a useful method I am glad my father showed it to me all those years ago!
Hi profesor. I've been trying to understand this problem for days.
I've come a long way, and from what I've gathered, most of the scientific consensus seems to flow towards explaining this behaviour kinda the same way you did. And even though when I first heard it I went "aha!", there is something that I just can't get my head arround.
If the thing which is driving the siphon it's this two facts:
*The outward tube side colummn of liquid falls because of gravity
*The rest of the liquid either follows it through water cohesion or through little vacuums created and pressure differences.
If those two statements are correct. Then Why does the exit of the tube NEEDS to be at a lower level than the reservoir liquid surface?
Doesn't those two conditions apply at any point in the tube where the liquid is falling?
Federico, good question. So one way to think about it is that the liquid in the output pipe is a longer column length so has a greater weight than that in the upwards liquid flow pipe. Some people think of the highest point of the tube as a pulley and the liquid as rope with a weight at either end hanging over the pulley. The weight on the heavier side will fall and the other side will rise. Not a great 'explanation' but hope that helps a bit if you think of the liquid as having cohesive forces throughout it (such as hydrogen bonds).
@@AnthonyFrancisJones oh! Then if the chain is lighter on the outward side of the tube, then the whole system Will just fall back to the reservoir, right?
Is a good analogy, it does give me some sort of ease of mind. Thanks for answering my question proffesor! Greetings from Argentina!
@@federicouliseslopez406 Yes, that is right, so the output tube and column has to be longer below the highest point in the tube, in other words below the input side.
Which would flow faster based on density? water, OJ or gasoline if all other specifications were equal?
Robert - that is a really good question. Not sure the density would make much of a difference as the liquid has to be lifted before it falls as it were (though I am going to have to think a bit harder about this...) I guess the real difference would be with different viscosities where gasoline should be the fastest flow rate. Very interesting question. Thanks for taking the time to watch and comment.
@@AnthonyFrancisJones my thought process was more density would mean more mass more mass would mean the effect of gravity would be stronger. Viscosity certainly would play a roll, yes.
Or is this a brick and a feather in a vacuum scenario?
@@robertcampomizzi7988 Yes, though remember you have to lift the extra mass against gravity in the first place. The distance between the liquid surface and the exit of the pipe vertically makes a difference until it is limited by viscous friction with the side walls of the tube. As with everything in physics, there is more going on here than my rather simple demo as you have pointed out!
@@robertcampomizzi7988 I think you are thinking of my Guinea and Feather experiment ua-cam.com/video/Ygq9LZmpDi0/v-deo.html
I just carried this experiment out and found that the only way to reverse gravitational effect is by using forced energy,,
This begs the question if its possible to create this forced energy by some way or means to incerting a propeller unit so when water is syphoned at the syphoning point the draw creates the energy internally to drive the flow faster and by switching the propeller in the opossit direction of rotation so drives the fluid flow up hill i assume this unit can be made fitted nano tech,
Its worth testing,, I assume suction can drove a propeller by forcevof gravity which in turn would be the driving force behind the flow,,a nano built in system that allowed to defy gravitational force by margin,,i wont claim it will full be 100℅
But would go some way to defining an equivocal and concise answer.
Good question. As ever the Law of Conservation of Energy, and thermodynamics laws/entropy are against us here so, as no system can be 100% efficient we would need to add some energy to the system to get the water to go back up from an external source. The skill is to make the external source look as 'invisible' as possible!
So it could be working sort of like a xylem in a plant?
Yes, possibly but really it is more a case of capillary action as the water mainly only goes upward. There is also the effect of water then evaporating away from the surface of the leaves. But, there are no pumps in a plant - just good old capillary action! The joy of physics, as you have noticed is you can use it in all sorts of different situations to explain what is happening. I have done a video on capillary action too that you might enjoy. Regardless, thanks for watching!
@@AnthonyFrancisJones Thanks to you too for the demonstration
I would say its just a vacuum effect. The liquid is creating a vacuum. It seems pretty simple really. Also gravity playing ita part. Think of it like a train going over a hill. If you have enough weight on the down grade it can pull the other part up with no outside force at all. With the liquid the pull of the liquid going down is stronger that the other liquid coming up. So maybe with a long enough hose and syphoning it up to the end you could make it pull uphill a bit. But your downhill would need to be longer into you higher glass. Would be tricky if possible.
Thanks for that. Yes, your train model is a good one as the train carriages are coupled as are the water molecules with intermolecular forces. There may be a lower pressure but not a vacuum as the liquid would immediately vaporise - you might have seen my Tea on Everest video - ua-cam.com/video/wIEsDY-EieE/v-deo.html In terms of finally flowing up hill - this is not possible with one exception, if the liquid already has some kinetic energy imparted to it. A bit like walking with a cup of tea and shaking it - the tea will go up hill over the cup walls. Thanks so much for watching and taking the time to comment. It is really good science to discuss things and how they work whether one agrees or not. Hope you enjoy the other videos too!
@@AnthonyFrancisJones I guess vacuum may be the wrong word to use. Suction would be the right terminology I suppose.
Many call it suction but really what you are looking at is a reduction of pressure compared to another place. I try to explain to pupils that 'vacuums do not suck' what happens is the higher pressure (and therefore moving particles) rush in. Really they have a higher mean free path in the direction of the low pressure but the vacuum does not magically draw (suck) them in!
Hello.. I want to ask.. Can the water increase its pressure when u make an tube arc that ishigher.
Imagine when 3 floors.
1st floor is the the outlet.
2nd floor is the water jug(source of water)
And 3rd is the water arc of the water pipe
We all know that we can directly get water from the source in the 2nd floor directly to the 1st floor..
The question is.. If we increase the height of the tupe upto the 3rd floor. It will increase?
Brilliant question! So, in pure syphoning the water flow is affected by the vertical height difference of the top water surface and the exit on the lower hose. So, raising the top of the loop higher but keeping the other positions the same will make no difference as long as the syphon is working. It's a really fantastic question you have asked and I really should demonstrate it at some stage. Thanks for taking the time to comment and keep thinking like this - that's what good science is all about!
why dont you pour the petrol into the tube to fill it up then sucking it. just tip the fluid into a smaller container to do so
Yes, good point. The tube we used was very narrow and by the time I had decanted some and then poured it into the tube it would probably be all over the place! To be honest, you get quite good at it and even if there is a bit of air left at the end that you suck, as long as you seal it briefly and then lower that end quickly it all works fine, without getting a mouthful!
Which branch of engineering did you study
I did Production Engineering - then a post grad in physics education at Cambridge, which was outstanding. I was also brilliantly taught at school - the rest speaks for itself Kerem. I of course started early as a child with brilliant support from my parents. I think my dad bought me an oscilloscope when I was 14!
@@AnthonyFrancisJones thanks for the explanation I am considering between mechanical engineering and electrical engineering. What would you say for a person who loves physics and would love to be able to build machines and robotics. Which branch would be better or can you share your knowledge about those practices
@@keremalp4627 Both are equally useful - best idea is to ask very careful about the courses before you choose. There are so many different engineering disciplines too so check all that are available to you. Two other thoughts - study one and specialise later. Also in the UK there are courses especially for robotics. Personally I am a great fun of 'get the basics and specialise later'. Hope that helps a bit! Most of all, and this is really important, do what you enjoy and the rest will come.
@@AnthonyFrancisJones thanks for the help
@@keremalp4627 Pleasure!
I wonder is there any possible way of siphoning so that the fluid is going basically in reverse? From downhill to uphill without a pump
Good question. Basically no unless there is a pressure difference that allows for it to happen but that would not be syphoning! Perhaps I should have lifted the output hose end to show where it would fail to work - above the inlet. To do what you ask it would have to gain gravitational potential energy from somewhere so something would have to allow that to happen and if it did it is not a simple syphon system but something more complex with another source of energy. Thanks for the question and glad the video got you thinking!
Look up a RAM PUMP
Yes that's a great piece of kit. My father always talked to me about them in the stream that we had.
Could it be related to the communicating vessels of Archimedes?
Thanks for your question Frank - you are thinking of something else - have a look at my video on Pascal's Law and I hope that explains it! ua-cam.com/video/PE5PV3F1-6w/v-deo.html
It’s not really flowing uphill if the liquid will end up at a lower elevation than where you syphoned it from.
Yes, I take your point - it is only flowing up hill for some of the path it takes. Now capillary action is a completely different matter so you might enjoy this... ua-cam.com/video/s2VNbrfM01k/v-deo.html
Yeah you are right scientists still argue about this simple thing
Good answer! Yes, you must always keep an open and enquiring mind with all things. Thanks for taking the time to watch and comment.
Great video
Thanks, glad you liked it!
Answear
Suction creating gravity force,,now reverse this so we can see it works both ways,,can you do it?
I will buy you a coffee when you show me gravity lift back to the same glass the orange juice came out of,,keep the glasses where they are.
Thanks Michael. I am sorry (for myself) as I am unable to claim a coffee at your expense (kind offer) as there is no way the laws of physics allow for this to happen unless there is an external source of energy. If it comes from the system itself there will always be losses (friction is a good place to start) so it can never work in that way. Shame, but physics does not allow us to share a coffee together!
This might sound crazy but i got thinking,,could it be possible with a hosepipe that a Nano apparatouse of some description like maybe a Nano rotary pump,or Nano propeller using force of gravity to drive the flow on and,above,,
Okay its clear a syphon,syphones from one bowle to another but lets say it was possible to create an aparatouse that could be connected onto or into a hose that would function from the waterfirce of gravitational effect to drive the flow up and beyond lets say?
6ft which in effect by all standards of a new developed product that would create new products,
I found on a simple test when you squease water in a soft object it creates force,,so i wondered wether that such force could be captured on routevto its host,,thus the gravitational effect with that force to so drive to a,set point,,,without the need for applying battery,electric or a fuel driven device,,only by gravitation and such a device that captures and pushes on that force isolating out a Ram Pump,,etc.
Yes, an external force (that moves) would help. Such as squeezing the hose with a valve in it to stop return (I am working on a Tesla Valve video at the moment). A ram pump is a brilliant device but still needs an external source of energy.
Orange juice is acidic and the top glass is on top metal can be charged with electrical force but now with ether and solenoid can transfer without pipe and that is how lower price of gasoline but what if it can be stolen ...that is why German engineering use diesel which is harder to stole than gasoline or air plane jet fuel
Great explanation you’re a great teacher
Thanks, that's really kind of you and so pleased you liked it and found it useful.
how is this possible?
It is an odd effect! Works perfectly well with water but I used orange juice so you could see it better on the video. Main thing is that the hose is completely full and that the container the outlet of the pipe must be lower than the inlet so overall the mass of the liquid falls. Thanks for watching!
Brilliant ! Fantastic video …
Thanks, glad you liked it and thanks for taking the time to comment.
Will the liquid climb up against gravity if we create a vacuum in empty cup (the higher one), I'ven't experimented it myself but I guess if the vacuum is strong enough it would pull the liquid back till the pressure become steady, right?
Good question Hamed - Yes the water would go up to the container with the vacuum - remember the vacuum does not pull the water up - the atmosphere pushes it in! There are also issues with it causing the water to boil (at room temperature too!) You will see me do this in this video - it is quite fun! Hope you enjoy it! ua-cam.com/video/wIEsDY-EieE/v-deo.html
thanks for the video!
Thanks again. I had fun making this and trying to explain this interesting phenomenon. Hope you are enjoying the videos. Plenty to choose from!
It happens because liquid will always follow the lowest part regardless of whether it needs to go up before going down. As long as the end of the flow is lower than the beginning. Everyone who has a rain catchment system that is then gravity fed on their homestead knows this.
Yes, indeed and that is a good application if there is a syphoning part but we need to explain 'why' liquids do this rather that they 'do' do this and that is not so easy, nor are all scientists in agreement about the cause of the process of syphoning. Such are the joys of science!
wow i didnt know that
I was hoping to see siphon uphill.
Sorry about that Joshua! The liquid does indeed go uphill without any 'obvious' source of additional gravitational potential energy but in the end the output must be lower. It is still very counterintuitive!
Thank you! Finally a great informative video!
Thanks - so pleased you liked it and thank you for taking the time to comment - makes it all worthwhile!
I need to reverse process ,is it possible ?? From down to up??
Good question! Not really I am afraid without an external source of energy. Now capillary action is a different matter - Here is a link to my video on that. ua-cam.com/video/s2VNbrfM01k/v-deo.html
@@AnthonyFrancisJones thanks for your kind reply, i use this capilary techiniq for my gardens. I am using this Hemp rope..
Great idea!
Thanks! I'm curious if you could somehow inject bubbles to prove the pressure theory.
Yes, that's interesting - I know that when a reasonably large bubble gets in the syphon fails. Gases can change their volume quite easily so this may be part of it as well as there being no cohesion forces between the molecules as they are about 2000 times further apart. I can visualise the kind of apparatus you are thinking of - if only I had more time! Great idea and thanks for taking the time to comment.
@@AnthonyFrancisJones
What you are asking about is called a "water elevator".
It uses are to move the water up.
Look for it on YT.
Also look up videos on trompe. Bell siphons also.
The tromp makes air pressure. The Bell siphon helps to empty your tank automatically.
You use the air pressure from the trunk to make the bubbles for your water elevator.
Blessings on your much success amen.
@@reypolice5231 Thanks again for this - it is a very interesting topic. I am reminded of Mine Craft - not that I know anything about it!
Show time⌚ lapse barometer with mercury😇
Yes, that would be a great idea!
Can we do reverse??
Krishansh, I am not quite sure what you are asking but it would not syphon to the upper container. However, liquids can flow uphill without going back down if that is what you mean - you need much smaller 'pipes' so have a look at my video on Capillary Action. Thanks for your question. ua-cam.com/video/s2VNbrfM01k/v-deo.html
IT'S MORE COOL IF YOU CAN RETURN THE JUICE FROM THE LOWER BOTTLE ....LOL
Yes, that would make a splash in the world of physics!
Wait no I just finished the video and I need my Orange juice to go from the bottom cup to the top cup
That would be a challenge! I guess a pump is the order of the day but you might be interested in the Mould Effect or Chain Fountain as it is sometimes known.
@@AnthonyFrancisJones
Please do some videos on the Trompe that was invented in the 1600s to create pressurized air to run forges and air pressure equipment.
Then with all the pressurized air you can move the water uphill with a device called a water elevator that pushes air up through a pipe filled with water and gets the water to go up.
All of it really interesting stuff and you would be great at showing it to your UA-cam fans.
Many blessings in your endeavors and success amen.
@@reypolice5231 Thanks for the suggestion - it is a very interesting device. I remember my father teaching me when I was little about the Ram Pump and saying how amazing it was as it seemed to work as if by magic but of course underlying good science! You are right - it is amazing how ancient these devices are. As an aside I have Hero's Engine on my long list of films to make too!
Who’s teacher is this loooll, why is he actually cool
Thanks Nathan, that's kind of you. Glad you enjoyed the video and most of all your science.
That's not an uphill siphon! That's just a normal siphon... Because the end of the pipe is lower than the other... Uphill siphon should be the opposite.
Yes, you are of course right - the interesting bit is why the fluid flows up in the first place without an apparent source of energy - of course there is but it is not very obvious such as having a pump or similar. Still a very interesting effect that is misunderstood by many. Thanks for watching!
@@AnthonyFrancisJones you're welcome sir.
I hope translate to Arabic
Great! I hope you can. I have had a go at the UA-cam translation but did not have much success with it.
Utube are you a good person by living waters my friend
Thanks and glad you enjoyed the video!
Annoying background sound, turn it off
Sorry about that. I have had a listen through again and don't seem to hear what you refer too. I know my large lab has quite an echo and it was filmed during the working day in a school. I now film with a tie clip mic which helps. Any further suggestions greatly received.
This is just what I needed thank you if I were your dad I probably would’ve just build a bridge and on top Then you could pour iteasily or make a regular siphon easily
Agreed - but the point here is we could fill up anywhere on the road or out in the fields easily!
നീ മിടുക്കൻ ആണെടാ
Thanks for commenting. My Malayalam is not up to much but if you are saying what I think that's kind of you. Hope you enjoy the physics here!
@@AnthonyFrancisJones i mean u r outstanding... bravo....
@@agintommankuzhi9554 Thanks very much - that's what I read and is very kind of you. Glad you enjoyed the video and do, as ever, enjoy your physics!
Its a difference in weight
correct title but wrong picture . i watch because the pic says it go up hill . ITS A TRAAAAAAAAAAAAAPPPPPPPP😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭😭
True! Hope you enjoyed it though! It is odd though that without a pump the water really does begin by going up hill. Thanks for watching.