Buoyancy of Sand demonstration-- Archimedes principle /// Homemade Science with Bruce Yeany
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- Опубліковано 11 вер 2024
- When sand particles are put into motion, heavy and light objects will sink or float in the sand and behave just like in a fluid. The moving sand can be used to demonstrate the concept of buoyant forces. However, due to the size and friction of the sand particles the buoyant force does not quite equal the weight of the amount of sand displaced by the submerged objects (Archimedes principle).
Please check out my other Homemade Science videos at:
/ yeanyscience
Homemade science is a collection of classroom tested ideas, suggestions, projects, and experiments that I have used in teaching physical science for the Annville-Cleona school district in central Pennsylvania. I am currently in my 38th year of teaching. My intention is to share these ideas with other teachers or anyone who has an interest in science. I have found that designing and building my own equipment has taught me more than any course that I have ever taken. I hope that you consider making or trying these experiements for yourself.
This is one of the most spectacular and fascinating physical experiments I've ever seen so far. Thank you, Mr. Yeany.
I really like this experiment also.
this reminds me of another experiment i've seen. kind of contradictory, but i've heard that each individual particle of sand in motion can act as a wedge to fall under a larger object and make it come to the surface. your video obviously demonstrates that buoyancy plays a role in this phenomenon, so does the shape of a particular object have a role to play as well? i'd like to see a follow up video including objects of all sorts of shapes and densities if that's practical
HI Joe, I don't know if the shape is also playing a role in the this but can try it, if so I will post it
It'd be great to see a "sand boat"!
The thing to remember is this is a demonstration not an experiment. It shows something that we already know is happening, we haven't formed any hypothesis, taken data, or even tested that data. This is as close to an experiment as a baking soda and vinegar volcano.
Demonstrations are very important to get students to think about whats going on and whats happening, but it is important that we stop blurring the lines between a demonstration and an experiment.
This was a very interesting demonstration though.
If any one you has used a sieve or strainer you probably wondered why this was happening and didn’t realize it, excellent video and ty for treating us
1:10 I just love your laugh
Is this why an earthquake can cause things to sink into the earth, depending on the composition of the ground? I think it's called liquefaction.
At the start of the video I thought that air was being pumped through the sand to get the particles moving. I wouldn't have thought of using vibration, but it's a much better way of doing things. Nice work!
Jefferson Allan, sand/gravel acting more like liquid instead of a solid has been the cause of at least a few buildings collapsing during an earthquake. The phenomenon is called liquefaction and is pretty cool.
D Krock jeez, hadn't thought of that. It's a good thing we rarely get earthquakes in Perth (Australia) because most of the city is built on sand
You kept saying "lighter" and "heavier", but you meant less or more dense. It makes no sense to say that sand is lighter than a steel ball; rather, it is less dense. I realize this is a very common mistake most people make, but as scientists, we need to "STEM" the tide of such imprecise speech.
Great! Every teachers should have the ability to build DIY tools.
Fantastic!!!. Can't be explained much simpler than this!!! Hoping for more videos like this!!
Another interesting experiment is buoyancy of floristic foam brick(Oasis foam). If it's lowered slowly into water all air escapes and it sinks, but if it's shoved into water quickly air gets trapped inside and it stays buoyant.
I discovered your channel few days ago and I can't stop watching Your videos. It's awesome !
thanks, glad you like it
same here!
This is so cool! I wish I had you as my science teacher when I was in highschool.
Excellent. Just found your channel. These are great teaching tools, and well presented. Subscribed!
thanks
Bruce.... you are amazing.. i really love your homemade science. i wish you all the best.... keep it up .
Thanks Sultan, I appreciate the comment
Again with another cool video. I always wondered why sifting raises some objects while lowering others.
your channel is very underrated
That's the way the earthquake is able to sink the whole building into ground in a matter of seconds on some types of sandy soil.
Mr. Bruce: thank you so much for the videos you've posted.
Extremely well done, fun to watch and, more importantly, it highlights and explains in a simple way fundamental science concepts.
Congrats from Portugal!
thank you
Thanks for this amazing experiment, graphically explaining buoyancy and density.
mind blown ... I never quite understood why buoyancy is limited to fluids only ... now I know it isn't... thank u!!!
We were just talking about if sand has buoyancy force and bumped into this video. Great experimental design. Many thanks.
mustafa turan I'm glad it could help, this is one of my favorite demonstrations.
This experiment is cooler than anything I did in high school science!!
It's not the weight it's the density
I think
@@GrodyMaroon "Density is mass per unit volume. Weight is dependent on mass, so density is dependent on weight."
No. First, they're both dependent on _mass,_ not weight. Notice in your sentence you said "density is mass per unit volume" (D=m/V) which doesn't have weight in it. Weight is the acceleration of mass due to gravity (F=ma, where a=g). Mass =/= weight.
Second, increasing mass only increases density if the volume remains the same or increases at a lesser rate. Because mass is associated with physical objects, increasing it will necessarily increase the volume as well of the new mass. This is why the density of a glass of water scooped out of the ocean is equal to the water of the entire ocean altogether (ignoring negligible salinity and mineral differences near land).
I disagree. Boyancy depends on density not weight. . .
For object of the same volume, more or less like the balls shown in the video, density relates to weight since the volume is the same (+-). Its just easier to explain this in terms of weight even if not 100% accurate.
maxsnts Yeah--but this minor difference makes huge differences when it comes to boyancy
Blowie it's weight if you compare it to an equal volume of sand
The 'strength' of buoyancy depends on gravity. gravity x density is weight per volume.
There is no boyancy in weightlessness.
I always know what's gonna happen in your videos based on the titles, but I still watch them because they're so entertaining.
When the motor isn't moving, the sand behaves a little bit like ice, because the particles aren't moving
I hope my son gets a good teacher like you.
Also, nice cover of Traffic for your soundtrack. I can't seem to find my way home, either.
Muchas gracias.
This is a great demonstration! Love your videos.
thanks
This appears to be similar to how quicksand works. The difference being the water in quicksand that helps to keep the mixture more fluid like.
my new favourite channel :-)
Awesome! These look so cool!
Brilliant demonstration! This idea is so amazing!!! oO
I think, that could explain in a way what's happening with quicksand, right? Each movement reduces the friction and you sink more and more, faster and faster...?...
if it ran long enough would you get different layers of sand?
Excelente !!
Buenísimos tus videos !!
Neat! I am confused; Is this demonstration analogous to, or an exact parallel to how bouyany works in a liquid? Would it be possible to acheive neutral bouyancy in the medium of sand, or does sand-in-motion act differently when floating/sinking objects, as in a binary up-or-down-only scenerio?
Will the sand remain solid if the shaking is just minimum, let's say on Richter scale of 1, can it not behave like a fluid?
thanks
Very cool
the distance of lift by the float in a tall cylinder of water from the bottom to the top equals the displaced volume times the height of the cylinder.
Does this have anything to do with the tale that the more you thrash around in quicksand, the faster you sink?
bg6b7bft Actually you can't sink in a quicksand, because sand+water is more dense that the human body. That's a myth.
Quicksand is a thixotropic fluid like catsup; its viscosity is inversely proportional to the shear stress placed on it. You will float on top of quicksand if you stay calm but will pull yourself under if you flail about.
здорово!
Спасибо
Awesome
Hi Bruce, what size motor and battery did you use for this demonstration? And approximately how much sand did you use? Thank you. :)
Which shows that quicksand isn't as dangerous as movies make you think it is
aaaaaaaaaaaaaaah you can never know
I'm sad like a steel ball drowning in sand but why is there sand in my bed? Oh Morpheus!
Does this experiment prove the existence of atoms and molecules ?
If the water molecules don't move at all, can a brick float at the surface of water, like the steal ball (that have a higher density than the sand) is floating over the sand without vibrations ?
Thanks for sharing this amazing experiment :D
AWESOME!!!!
Great experiment! Can you provide some instructions on how to construct the bucket/motor/power source set up? Also, what other objects would work well in the sand in addition to the steel balls vs plastic balls? Thanks!
+Brian Lappin Hi Brian, I have a write up on this piece with instructions on how to build it, send me an email address and I'll forward it to you. Other objects that work well are nuts and bolts, lead sinkers, foam peanuts, ping pong balls
+Bruce Yeany (Yeany Science) Thanks! My email is BLieve7_13@yahoo.com
very epic! :0
Hi, no one drew your attention on one mistake, it's not about how heavy is the object but how dense it is.... anyway very nice channel, I'm sure that you have all kids attention during lessons which is not so easy with kids nowadays :)
I missed it too, thanks
amazing.
Clear and simple! Would you have any ideas about buoyancy for a science fair project that's not too complicated? Thanks!
+Michelle Ganoza Hello MIchelle, This project might not be too hard if you have some tools and materials available. I can send you instructions on how to build it. Some very simple ideas might be layered density columns of different density liquids, perhaps a demonstration of Archimedes principle and show how the depth that a floating objects sinks to is related to the equal volume of water
@@YeanyScience Can you please send the instructions to make this model
super cool
thank you
So if you want to build a house on sand it has to be built like a house boat?
if a bucket of water is balanced by a counter weight and the float is held in a fixed position above the waterline of the bucket as a force is applied downward on the counter weight the bucket goes up but there is no work done by the float to resist the motion as the float reach the bottom of the bucket. this is because the lift of the balanced bucket upward movement against the stationary float is equal to the float going downward as the water goes up at a equal speed the net force between the two is zero. its like a pendulum on wheels. the pendulum goes one way the wheels the opposite way but the net force of motion is zero. by this you can reset a device that will behave as if the float was moving upward against a infinite distance. in other words you are creating the equevalence of a reactionless drive powered by gravity. it produces a net force against the earth but the reversal of that have a zero net force. that means that the total output of the combined two create a infinite amount of energy. the violation of conservation of energy is clear enough but as such concept is assumed a closed system to begin it therby render it impossible. this theories of energy conservation was invented around 200 years ago and was based on the science of heat and how a hot body can only flow one way from hot to cold as a closed system. such a idea of heat transfer can only go one way is based on a machine that operates from within a closed system. the truth is that it takes zero energy to transfer a equal amount of heat from a cold body to a hotter body but it takes a force of a given stored amount of energy to exhange it. in a perfect system the exhange cost zero energy as the energy used can be recycled over and over to pump the heat from a colder body to a hot one. the question is in a reactionless drive do we really create energy. we either create energy or we convert a invisible form of energy into a usable form. the idea that energy can never be created or destroyed may not even be true expecially with the idea that the universe itself was supposly created from nothing.
how didn't you say density in a video about density
2:15 can this vibrating sand box be used to clean spoons n forks?
amazing
Very coool !!'
Were I self taught ?
How sand become in motion ?
What song is playing at the end?
Mr. Fox the song is Blind Faith, Can't Find My Way Home.
I searched through the comments hoping someone would recognize that classic song. You did not disappoint.
Its like quick sand
Hi, Is it possible to get a description of how the motor/sand container is made?
yes, send me an email at bgoknee@comcast.net remind me what you want plans for and I will forward them
Is surface tension the same as the sand static fraction
No. Surface tension is due to a particular arrangement of molecules at the interface between two media.
Hi Bruce!, There's a science fair coming soon in my school and my team an I, would like to perform this experiment, do you think that you can help us with the materials that we need?
Yes, Send me an email and I can send you a set of building instructions with pictures
Hi again!, We already did the experiment the way you did it and it worked perfectly, thanks a lot for the gesture and taking time to read the comment!
@@YeanyScience I also wish to know the power of the motor.. I tried at home with some rice granules but didn't work..how do I send you a mail? I am a little clueless as I don't know your email Id.
just wow
What kind of sand are you using for this demonstration? I've been trying to replicate this for my students but the sand I'm using won't replicate the demonstration.
HI Megan, I have run workshops where teachers have built these and we have play sand, possibly the motor is not strong enough to give the container the vibrations needed, can you try a stronger motor or up the voltage. The sand that I am using is black sand, my son lives on Maui and sent it to me years ago. Some craft stores sell larger grained sand that you could try. I haven't tried it but have had a few people tell me they used rice instead of sand. If you send me an email address I can forward my building instructions for it if you think that would help
@@YeanyScience Thank you! My email address us meganplouffe@gmail.com. I believe I need a larger motor since the one I am currently using is only 3 volts.
information has been sent@@meganwatson4543
@@YeanyScience i am trying to build a replica also,i would love to get the drawing of the electrical circle . can i work with beach sand? or dry sand is preffered?
What type of sand is that?
What type of motor are you using for motion effect? Thanks
DC project motor, 280, very common toy motor1-6 volts
Im the first one to comment! What a honour ! Exelent job Bruce!
franco brizuela Thank you Franco, I hope that you find them helpful. Good luck with teaching physics.
Thanks a lot Bruce and good night¡
you da man!
What about the brasiliano nut efect in particles
I was wondering the same thing! What about the brazil nut effect, +Bruce Yeany?
A small rock is lighter than 1000 liters of water but still sinks. Because it's denser, should've used the term density not weight.
Would this also work if the sand was under water/ wet?
I think it would have too much friction
Why earthquakes are bad in sandy areas with structures.
hello bruce, i am a student and wish to do this experiment for my class stem project and was hoping that you could suply me with the instructions. thank you so much
email me at cassiechays@gmail.com
+Cynthia Hays Hello Cynthia, it is on the way
@@YeanyScience can u send it iny my acc too? hillaryartajos11@gmail.com
Sir,Can You Please Tell Me which Type of sand Is this ?
Hello Arpan, it is sand that my son send from the western part of the U.S. I'm not sure where. Other sand will work in this device.
If you still can, will you send me those instructions. I guess you need my email, right? Also, I had an idea today about an alternative method. Would the base and vibration of a speak have the same effect?
+Brian Lappin Never mind about the email - I already gave you that!
*greater than the DENSITY of the styrofoam. Density and weight are not the same.
can I use any kind of sand I mean construction Sand
yes
if you place a float inside a bucket of water the bucket weight the same what ever the float is there or not so how can the float equal the weight of the displaced water. it have nothing to do with it. its not the displaced weight that pushes the float up. its the water that is sinking below the float and pushes the float up. just take a bucket of oil and pour water down into it. you will see the water is pushing the oil upward. the water is heavier than the oil so it will sink to the bottom and displace the oil. the float in the water bucket is the same. the water is sinking below the float and pushes the float up because the water is more dense than the float. its a sinking behavior that is lifting the float. it have nothing to do with a float equal to displaced volume of water.
i want to know how you made it !!!
please!!!!!!! please!!!!!!!!!
reply or make a video
please!!!!!!!! please!!!!!!!!!
send me an email request to bgoknee@comcast.net and I will forward the instructions
What is this music at the beginning?
It is from an Apple computer file, I don't know the name
DOES ANYONE KNOW IF THIS IS A SPECIAL SAND???????????????????????????
it doesn't need to be special sand, you can do it with uncooked rice
„the brick weighs more than the water“ What water?
the brick weighs more than an equal volume of water
@@YeanyScience Yes I knew that and I knew that you knew it. I asked the question because my pupils say the same like you did and when I ask them "what water", most can't give the right answer. BTW I like your videos very much!
Very good, Bruce. I'm always looking for new ideas for demos. I always knew solids can provide buoyancy, but hadn't thought of this very simple setup.
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I'll be looking at your other videos now...
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Regards, ScienceAdvisorSteve
www.challengerillinois.org
lets vibrate the desert and treasures will merge up themselves!
I think I saw that ping pong trick somewhere down in Mexico...
"Quicksand"!
+Observ45er, I love this experiment, I should do a sequel with alternative materials. I also have a larger one with a large plastic bucket and stronger motor.
Bruce Yeany I like it very much as well. I like the way it works into one of the primary characteristics of a fluid: that they flow and conform to their container (which also means to objects immersed in the fluid). This allows the sand to flow and act like a fluid. I wonder if Cheerios would work, or a large selection of mixed nuts. I've heard that Brazil nuts tend to rise to the top..... a solids "density column" similar to Steve Spangler's liquid Density Column, but it forms itself. (the liquids are tricky to pour on top of each other to prevent mixing of the miscible ones).
... or ...
Just different sands, or that glitter, or Iron filings... There may be some secondary effects that could confuse this demo. Lots of interesting variations to explore.
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Gee! Various balls are kinda' boring, no? ... Does a little Lego man float in your quicksand? I have lots of Legos !! HA! HA! Start the demo with him buried, then turn on the motor!
WOW! a QuickSand Cartesian diver !!??
I also have three offset-weight motors from a vibrating car-seat cushion that have been looking for a solution for quite some time... Sorry, that pun was completely unintentional! I was thinking "A solution waiting for a problem" when I wrote it. I should have written "waiting for a problem", but, strangely, "solution" came to mind first.
...
That reminds me of a saying that we frequently used in Motorola Engineering when things went wrong: "Once again we've snatched Defeat from the jaws of Victory."
... or ... One I coined:
They say that we learn from our mistakes. Well, BOY! Am I learnin' NOW !!.
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You are to be commended for your true creativity in your demos.
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Regards, Steve
Instead of cheerios, I would go with Kix, the round shape is going to let them shift positions a bit better. You can also try rice, quinoa, salt, sugar, dried beans, etc, I haven't tried fine powders such as flour, so I don't know how they would work. Also tried other shapes and figures in the sand, I've used cigarette butts and bits of foam food containers and talked about people hiding their trash at the beach only to have it raise again. A small coffin to explain why you don't want a cemetery in a flood plane. I think this happened in New Orleans during their flooding.
It would be interesting to try a density column of solids. I have some thinner plastic tubes that are clear on the sides allowing you to see the levels. You can also do this experiment manually agitating the medium by shaking rather than using a vibrating motor, but it's not as fun.
Steve does a couple of density columns, one with different types of liquids that separate out to their respective densities, the other one is where he uses different concentrations of sugar water. I keep telling him to switch it to salt, then you can let them sit for a few weeks without them getting a mold on top. It's interesting to watch the colors slowly diffuse. I do this in a five foot tall tube with five colors, it is beautiful. I have a nice little write up with a picture of the big one if you'd like to see it.
Bruce Yeany Coffin, cute.
Very good on all of that. I think the grainer things will be better since flour can pack pretty tight. You need the ability to easily shake particles loose. I heard many years ago that real quicksand has a spring under it to keep the grains loose from the slow upward water movement.
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I got Spangler to correct his "Soda Can Jump" explanation. He was incorrectly using Bernoulli when it's simple pressure.
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I've contacted his team a couple of times about his Bernoulli explanations, but they seems reluctant to correct it.
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Regards, a different Steve
is this why we sink in quicksand
+Boon Hui I would guess the action would pretty much be the same, the water in the quicksand would allow the sand particles to slip past each other. I never saw it but imagine it would be something like stepping in mud.
+Bruce Yeany (Yeany Science) From what I've heard, quicksand is caused by an upward pressure, or slow flow of the water helping to keep the sand from settling. A person should be able to use swimming motions to keep from sinking, just as in water.
Don't use helium balloons, it's a really futile use of a valuable gas!
Thanks for the comment, I agree, I usually use Hydrogen but more people understand about Helium being lighter than air
Just on a positive note, I didn't know about buoyancy in agitated sand! I'm an engineering student at university, but I still enjoy your demonstrations!
Glad I could help
So weird!