Dude I frikin love your channel. What are the odds I would find you here. My name isTrevor Johnson, remember me bc I'm gunna change the world some day.
Hey, are you here too??? Cool! I totally love your videos. Also, making one like this can maybe shoot you into space if it hase enough force. However the G Force would be so high that no one would survive that. Also you couldn't get into orbit. Anyway, a fun idea! :P
Build two of these, mount them one pointing to the left, one to the right, on a plate strapped to your back: Fairy wings. Add glow in the dark paint and high intensity UV LEDs pointed at the string close to the shooter's wheels: Halloween costume.
good idea marcelo glenadel .... how about replacing the painted glow in the dark string and the UV LEDS, replace with a continuous loop of LEDs, and rig it so that the point of contact with the rollers is also the point of contact for the electrical supply to the LEDs.???
Sadly, I have a feeling that the string would be going too fast and the flames would be blown out. If that wasn't the case though, that would be awesome.
This was really impressive. I would like to see you use a dye or some other color indicator on the string so we can see just how fast the string itself is moving compared to the wobbles you put in the string by moving it.
It's science teacher like you that give hope to our world and encourage more students to explore the science of our universe. Thank you for being being a great and engaging teacher.
You, good sir.....are an excellent educator. You remind me much of my 6th grade teacher, Mr. Salyards. Passionate. Back in 85, with his complete guidance, we built a "Laser Room".....as we called it. He explained to us how to make holograms, and we did.....in 1985!! Awesome! Here I am now, digging on this vid. thanks, for taking me back.
I believe that those "sprockets" might get a little too hot and maybe melt from all the friction. I don't study physics, but I believe I am right. Might be a cool experiment, though.
If I had to guess, I would say that the friction caused by your fingers is slowing the string down slightly causing it to back up on the bottom due to its momentum. The string can't be compressed so it manifests as a wave.
Mr. Yeany. As one of your former students, I must say your science still impresses the Heck out of me. I'm glad this showed up in my recommended videos.
Hi Dustin, thanks for the comment, it's nice to hear from you. I thought I'd make a few videos of some of my toys at AC and as usual I got carried away.
No video needed. Intro blew my mind already. Immediately liked, subscribed, and even hit the little bell icon (which makes the youtube algorithm feel all warm & fuzzy from what i hear!)
I bet you're an amazing teacher, you have a great ability to demonstrate science in a way that's fun and interesting. I'm sure you've made you mark on the youth
I keep explaining to friends how a space escalator would work and I refer to these hand held toys from the 90's and nobody has ever heard of them. thanks, now I have a vid to show them.
I'm thinking the same thing, this looks like it agrees with Mehdi's explanation. In this case the pulling force from the weight of the chain is replaced with the constant pulling from the motor. Mehdi showed that the kind of chain or distribution of masses didn't matter, with enough pulling it would make an arc.
Very nice. It would have been even nicer if it would've answered a few inevitable questions: * Why is the perturbation on the outward part mirrored on the inward part? * Are the waves moving at the same speed as the string? (I guess no, because the waves are moving from the engine towards the end of the loop on both sides.) So what is the speed of the waves in the string, and how is it calculated? * Why is the motion ov waves happening on not only the outward part of the string but also the inward part of the string? * The string shooter was shooting (outward part) on the top. How will it behave if the ourward part is at the bottom? And I haven't even started thinking yet... Which means your video IS awesome, beacuse it made me ask a lot of questions, and it would be nice if you could make a follow-up video with the answers!
Yes, the launch loop is about that big and require three nuclear power plants at each end to power it. I was thinking about doing a larger (than the toy) scale one with a modified lawnmower engine as a summer project. The goal would be to show that you can (or cannot) suspend a platform from the inertia of the string (or wire), tethered to the ground. There is a fundamental principal of statics that says you cannot put a load on a wire, and I believe that is why nobody serious has ever bothered to test it out. In any case, failing or not, i think it would turn out to be a fun video to watch
***** First, be careful, as more energy You pump into the wire, the more consequences of accidental contact with foreign objects. Second, in static you cannot push the wire, but this case is nothing but static.
azgarogly Yes i know. Safety is important since this thing will probably store enough energy in the wire to be potentially lethal. I haven't done the math yet but i figure the full power of the lawnmower deposited over a quarter of a second would equal the energy of a .44 Magnum. And yes, that was kind of the implicit point, this is not a static reference frame. But that is the standard answer i get if i ask a mechanical engineer.
By coloring the string in glow in the dark paint you have just given me the ideal way of creating the illusion of firing a semi controlled stream of particles from the end of the ghostbusters proton pack prop, ill have to try it out. Thanks!
Bruce I wonder if you could modulate the wheel speed (or elliptical wheels) to create weird shapes of the loops. You may be able to generate standing waves on the loop like the oscillations of electrons in the Bohr atomic model. Great video.
It was mentioned, string moves around 25 mph. 11 meters per second. Given a string is 5 meters long, the red dot would do 2 revolutions per second. Barely visible on video, I guess.
I should be able to do that, if you listen at 1:50 you can hear the splice clicking as it goes through the little plastic tube. I am planning on making a bigger one, not sure if I am going to use one motor or two, or possibly hand cranked, we'll see how it comes out
I had plans for them and they were lost during a computer crash. one of the few sets that I didn't have back ups for. I can take some pictures of it for you
Will there be a set of how to instructions? I think I really just need some motor specs so I know what DC motors to buy and what the drive shafts should look like...
We can see that the motors run off a total of 4.5 - 6.0 V DC (3 - 4 batteries). If the wheels are 1.5" diameter, and his estimate of 25 mph is accurate, then the motors need nominal output of ~5,400 rpm.
@Bruce Yeany Awesome Video! Thank you so much for sharing! Might you be able to help understand something? That wave movement at the top I understand, but why does it move out at the bottom? How does the force applied move backwards from the direction that the string itself is travelling?
+Bruce Yeany +L.Y. G. -- Touching the string changes the tension in the string loop. As it sounds like the sting completes about 3 loops per second, it should take about 1/3 second for a disturbance at the Launch End to propagate all the way around. Looks to me like it does. _Hypothesis:_ Wave speed is proportional to string speed and loop tension. Repeat the experiment with Beaded Chain, which will allow longer loops due to less aerodynamic drag+more mass and momentum. Vary the loop length, observe time for disturbances to propagate. Look at video frame-by-frame to get more exact timings. [Note: it is also known as Ball Chain. See www.michaels.com/bead-landing-ball-chain-spool/10338105.html for example.]
It's not science until you make some predictions and test the hypotheses! Why does the wave not propagate as fast as the string does and why don't the waves go all the way around? Would they go all the way around if the curve at the far side would be less tight?
Totally agree. atleast give/share some understand you learn from an experiment. Instead of showing of something happening because its "cool" and then just say its science.
Setekh. Guys, this is not "string theory" in University. Its what kids get (as a little extra i imagine) in "science class". Its the kind of motivator that leads some kids to be interested in the science behind it. If you listen to some of this teachers other videos, you will see that he actually asks kids to predict what will happen if so-and-so is changed.
As usual I am not sure who has the most fun in your classes; you or the kids. However, If my basic understanding of physics is correct the string is being pulled through the wheels, not pushed. The resulting dynamics of the string is due to its inertia. I was always lead to believe that the only two pushing forces were gravitational and magnetic. Just the same it is a fun machine that illustrates many properties of physics. Good job.
Why? Because of waste? If so, don't worry, this is an educational tool. It's most likely only used once a month or even once a year. Using rechargeable batteries wouldn't make much of a difference, just like with clocks and remote controls.
Also, a lot of people don't know that alkaline batteries have a low self-discharge rate compared to rechargeable ones. A lithium Ion battery has the lowest self discharge compared to other rechargeable batteries. It loses 24% per year. An alkaline however loses only 3% per year. The champion is primary lithium which only loses 2% per year. That's why digital clocks can run for years using alkaline batteries
Awesome video! I look forward to making one for my boys to play with. I can tell you make school amazing for your students. Thank you so much for that.
1) Can you tilt the loop sideways? 2) Even with this device, you could not stop the wave. Do you think you can make an experiment were you can manage to stop it? 3) And this baffles me the most. On the slow moving "gravity assisted" version the downstream side of the loop seemed like solid. Why we observe here slow moving wave even on the downstream side?? I expected it to be at least as "solid" as on the vertical version.
woowooNeedsFaith the "new" loop forms in the orientation that the string gets shot out at. if you try to move the launcher too abruptly you can tangle the in feed sometimes but that's about all.
Dude, we could totally turn this into a space elevator, just shoot a metal cable instead and pass some current through it, you can ride it out to space, it's awesome!
Javier Chiappa I think you're under thinking the requirements for such a task. First off, the power needed for such a feet would be through the roof. The string in the video is about 16 ft in length whereas the cable to reach an appropriate height would need to be about 70,000+ kilometres long. Don't forget you're trying to propel this thing into space from a single point of contact. Even if you could get this cable to create a loop large enough to reach a station in geo synchronous orbit, to utilise it would need to attach a container to the cable whilst its spinning going from 0 to a few thousand meters per second almost instantly, this would throw the cable off course possibly pulling it out of the sky. I could go on and maybe I will if you want me too which I doubt but I'm tired so maybe some other time
212superdude212 And one would have to factor in the fact the Earth's rotational forces and let's not even consider the forces of weather. Sad we don't teach kids the math of physics. It's essentially the elevator cable problem. We have built tall buildings but an elevator can not go from the ground floor to the top floor. Why? The diameter of the cable would have to be so large the wight of the just the cable needed would exceed the strength of cable and the cable would break. This is a problem already exists in the tallest buildings in the world. If we can't do it for a building not sure how it could be done to get into space.
You know what would be a good variation of this demonstration and turn it into an experiment? Have multiple string launchers and use different lengths of string, and strings of different diameters.
I really enjoy the Content you are putting out on your channel. I'm currently enrolled in my second level physics course at my state university. I really wish we had access to these type of demonstrations during lecture! It would make the study of physics much more interesting. Wave motion, inertia, angular properties, momentum, and projectile motion can all be taught by this device. Great work, keep it up. I'll show this to my professor and see if he likes your channel.
found the part after @1:50 the most interesting: when touching the rope on the top it also simultaneously moved the bottom. More explanation on that would be nice.
There's a concept called the "launch loop" that's being seriously considered as a future megaengineering project. Basically, it's one of these but with a circumference of 4000 kilometers that reaches up to an altitude of 80 km above the Earth's surface. It'd be a massive piece of maglev track suspended in the air by a heavy string spinning inside of it at 14 kilometers per second. This would allow us to build a normal electromagnetic mass driver floating 80 km in the air without using billions of metric tons of material to support it's massive weight. Essentially, this would enable us to launch things into a 500km circular orbit using only 120m/s of deltaV instead of the 10,000 to 14,000 m/s modern rockets use. In fact, if the payload were allowed to accelerate past 3g (which is relatively comfortable for humans), it could be accelerated directly onto an interplanetary trajectory without using a single drop of fuel.
Sean James That would be sweet. But the cable would be crazy. We would need to have some exotic materials to have a cable like that strong enough. It'll be awesome to do so though.
Mr Rishi The Cookie The cable could be made of modern materials easily. As long as it's accelerated up to speed at a modest rate, there'd be no seriously damaging force acting on any point of the cable that can't be damped out by servos. Damaging forces would be like the waves he created demonstrating this small version, except they'd be caused by gusts of wind, and servos could be used to cancel out such waves before they can do damage. A huge number of these servos would need to be disabled before cable failure would even be possible.
no knot. I used a small flame to melt the ends of the string and them stick them together while still hot. I wear leather gloves as I do them and roll the new joint between my thumb and finger to smooth it out.
Well gee, now I know exactly what I'm making the grandkids for Christmas- thanks for the inspiration, Bruce! BTW, I just love your videos- so much science-y fun! :D
Now we need to build a realllly big one that goes into space!
Dude I frikin love your channel. What are the odds I would find you here. My name isTrevor Johnson, remember me bc I'm gunna change the world some day.
wooo
Hey, are you here too??? Cool! I totally love your videos. Also, making one like this can maybe shoot you into space if it hase enough force. However the G Force would be so high that no one would survive that. Also you couldn't get into orbit. Anyway, a fun idea! :P
en.wikipedia.org/wiki/Launch_loop
Yes, yes we do.
my best idea is retro fitting a electric nerf blaster to shoot the string. also why is there a tube at the bottom?
Build two of these, mount them one pointing to the left, one to the right, on a plate strapped to your back: Fairy wings. Add glow in the dark paint and high intensity UV LEDs pointed at the string close to the shooter's wheels: Halloween costume.
Or you could be(e) a giant insect with all that noise.
Marcelo Glenadel Fairy wings? More like condoms.
good idea marcelo glenadel .... how about replacing the painted glow in the dark string and the UV LEDS, replace with a continuous loop of LEDs, and rig it so that the point of contact with the rollers is also the point of contact for the electrical supply to the LEDs.???
Put between legs for big peepee
Light it on fire?
anton arnqvist I want to
anton arnqvist probably have to soak it in gasoline first
Sadly, I have a feeling that the string would be going too fast and the flames would be blown out. If that wasn't the case though, that would be awesome.
Make the string out of firework fuse... string... s
Nabre Labre soak it in alcohol
It’s awesome to see someone this passionate about spreading knowledge and making it interesting for anyone to enjoy...thank you for being you
This was really impressive. I would like to see you use a dye or some other color indicator on the string so we can see just how fast the string itself is moving compared to the wobbles you put in the string by moving it.
It's science teacher like you that give hope to our world and encourage more students to explore the science of our universe. Thank you for being being a great and engaging teacher.
thank you
paint half of string red to see the speed.
Arnis Tarassu it would just look pink
900bz ok.lets paint them white and transparent.
Would it not just look white?
Glow in the dark? It'd look cool at least.
And either half colour would work for testing if you have a high speed camera anyway.
Use a stroboscope to see the speed 😉
Steve Mould sent me :) Simple design that is easy to duplicate!
so this is string theory…
Unfortunately being verified doesnt make you funny
@@5446isnotmynumber well said
You, good sir.....are an excellent educator. You remind me much of my 6th grade teacher, Mr. Salyards. Passionate. Back in 85, with his complete guidance, we built a "Laser Room".....as we called it. He explained to us how to make holograms, and we did.....in 1985!! Awesome!
Here I am now, digging on this vid. thanks, for taking me back.
thank you
Please someone build bigger version and instead of string use extended chainsaw chain. It would be terrifying tool.
Great idea. We just need to use sprockets that interlock with the chain instead of rubber tires.
I believe that those "sprockets" might get a little too hot and maybe melt from all the friction. I don't study physics, but I believe I am right. Might be a cool experiment, though.
Why would they? Chain drives are already a thing. Gears that spin against each other at speeds higher than this already exist.
You need help.
if they would melt.. my motorcycle would be in some trouble when i use full rpms
as a teacher you really inspired me and my love for all things science. we need more people like you Mr. Yeany
thank you Dale, that makes my day
What is the mechanism for perturbations on the top bring mirrored on the bottom?
Yes, I wondered that - Anyone?
That is a good question, at the moment I don't have an answer
Brent Lewis waves propagate faster than their substrate.
Cameron Sours At 25 mph, that spot you see on the bottom is probably the actual spot that he initially tapped (when it was at the top.)
If I had to guess, I would say that the friction caused by your fingers is slowing the string down slightly causing it to back up on the bottom due to its momentum. The string can't be compressed so it manifests as a wave.
Mr. Yeany. As one of your former students, I must say your science still impresses the Heck out of me. I'm glad this showed up in my recommended videos.
Hi Dustin, thanks for the comment, it's nice to hear from you. I thought I'd make a few videos of some of my toys at AC and as usual I got carried away.
WHAT IS THIS WITCHCRAFT??!
tenkikun she died from playing with a stupid string toy, wait you don't think...ut..oh!
Pikapetey Animations why I see you everywhere
Booooooriiinggg
Pikapetey Animations ayy
Fits your profile pic :P
Steve Mould sent me here, and I am very grateful to him-subscribed and already hit the bell!
Thanks for stopping by
Where do you get the string that's in a loop, or do you make it? In my mind, it wouldn't work very well with a knot in it.
it is a nylon string, I heat the ends and then roll them together while still how, of course I am wearing gloves as I do this
Bruce Yeany thanks!
No video needed. Intro blew my mind already. Immediately liked, subscribed, and even hit the little bell icon (which makes the youtube algorithm feel all warm & fuzzy from what i hear!)
Shout out from Steve Mould's channel!
I bet you're an amazing teacher, you have a great ability to demonstrate science in a way that's fun and interesting. I'm sure you've made you mark on the youth
This looks so unreal!
this is how magnet , electric, and gravitational waves.. along with every other wave travels thru space..well done..doc johnny
is this "string theory"?
LOL yes
@@YeanyScience XDD
wahahahaha......wait. what....!!!!!
underrated comment
No, it's 'string fact'
I keep explaining to friends how a space escalator would work and I refer to these hand held toys from the 90's and nobody has ever heard of them. thanks, now I have a vid to show them.
glad I could help
Does this have any relevance to the chain fountain debate?
I'm thinking the same thing, this looks like it agrees with Mehdi's explanation. In this case the pulling force from the weight of the chain is replaced with the constant pulling from the motor. Mehdi showed that the kind of chain or distribution of masses didn't matter, with enough pulling it would make an arc.
Very nice. It would have been even nicer if it would've answered a few inevitable questions:
* Why is the perturbation on the outward part mirrored on the inward part?
* Are the waves moving at the same speed as the string? (I guess no, because the waves are moving from the engine towards the end of the loop on both sides.) So what is the speed of the waves in the string, and how is it calculated?
* Why is the motion ov waves happening on not only the outward part of the string but also the inward part of the string?
* The string shooter was shooting (outward part) on the top. How will it behave if the ourward part is at the bottom?
And I haven't even started thinking yet...
Which means your video IS awesome, beacuse it made me ask a lot of questions, and it would be nice if you could make a follow-up video with the answers!
3:35 where'd the second to last popsicle stick Go?
right?
What a fascinating gadget. It's the first time I have seen this idea - and that's after a LOT of watching gadgetry on RUclips.
There's gotta be a way of doing this at a much larger scale...
They even want to launch things in space with that kind of loop. Around 2000 km long and 80 km high.
Yes, the launch loop is about that big and require three nuclear power plants at each end to power it. I was thinking about doing a larger (than the toy) scale one with a modified lawnmower engine as a summer project. The goal would be to show that you can (or cannot) suspend a platform from the inertia of the string (or wire), tethered to the ground. There is a fundamental principal of statics that says you cannot put a load on a wire, and I believe that is why nobody serious has ever bothered to test it out. In any case, failing or not, i think it would turn out to be a fun video to watch
***** First, be careful, as more energy You pump into the wire, the more consequences of accidental contact with foreign objects.
Second, in static you cannot push the wire, but this case is nothing but static.
azgarogly Yes i know. Safety is important since this thing will probably store enough energy in the wire to be potentially lethal. I haven't done the math yet but i figure the full power of the lawnmower deposited over a quarter of a second would equal the energy of a .44 Magnum.
And yes, that was kind of the implicit point, this is not a static reference frame. But that is the standard answer i get if i ask a mechanical engineer.
***** According to Google calculator 3.5 horsepower * 0.25 seconds =
652.487388 joules
More like .357 Magnum :)
By coloring the string in glow in the dark paint you have just given me the ideal way of creating the illusion of firing a semi controlled stream of particles from the end of the ghostbusters proton pack prop, ill have to try it out. Thanks!
What would happen if you put a rubberband string instead of a simple string?
Awesome idea^^
Thanks for sharing all your experiments!
I wanna build one
You really have something here, I love it. It could be used in music performances or something, it really catches the eye and has many possibilities.
Bruce
I wonder if you could modulate the wheel speed (or elliptical wheels) to create weird shapes of the loops. You may be able to generate standing waves on the loop like the oscillations of electrons in the Bohr atomic model. Great video.
Man...
You gave me the biggest inspirational clue for making fire-ish movements on 3D simulations!
Hella thanks
Marcos, glad I could help
i wish you were my science teacher
same
He is. Just not formally.
Thank you for sharing your fun and amazing invention!
Could you upload a short video with a little red dot on the rope, so we can get a gist of how fast it is actually spinning/moving?
It was mentioned, string moves around 25 mph. 11 meters per second. Given a string is 5 meters long, the red dot would do 2 revolutions per second. Barely visible on video, I guess.
I should be able to do that, if you listen at 1:50 you can hear the splice clicking as it goes through the little plastic tube. I am planning on making a bigger one, not sure if I am going to use one motor or two, or possibly hand cranked, we'll see how it comes out
@@YeanyScience what speed rpm motors are these?
idk
This guy would honestly be one of the coolest science teachers in the world
this is like a never ending version of dropping thin chain out of a cup
this guy loves his job, that's the kind of goals in life i wanna get to
Wonderful as always! Any chance you would show how to make one these so to allow us to pass on the magic of science?
I had plans for them and they were lost during a computer crash. one of the few sets that I didn't have back ups for. I can take some pictures of it for you
Dang computers! That would be wonderful. I thank you Sir.
I'm interested about these pictures too
thanks for the note, I haven't seen imgur before but will check it out
I have had quite a few requests for instructions, I should have some available in a few days
you are my favorite teacher now
what on earth. if the string speed is 25mph, how come the wave propagation is so much slower? amazing.
correct
Will there be a set of how to instructions? I think I really just need some motor specs so I know what DC motors to buy and what the drive shafts should look like...
Greg Burns I second this request. I would very much like to build one of these for my Pops and nephew to play with.
We can see that the motors run off a total of 4.5 - 6.0 V DC (3 - 4 batteries).
If the wheels are 1.5" diameter, and his estimate of 25 mph is accurate, then the motors need nominal output of ~5,400 rpm.
yes, I am working on a set of simplified plans or video for this
When your doctor says you got 4 minutes left to live
your are like “How much time do I have?“ and your doctor be like “6“
“6 what?“
“5, 4“
“omg“
“4:20 blaze it“
lights bong
.... I ask him if the Nurse is in a relationship.
madscientistshusta that's most of humanity for you, unfortunately. This is why we need a mars colony.
Very Cool. Now I have to build one so I can have some fun too.
@Bruce Yeany Awesome Video! Thank you so much for sharing! Might you be able to help understand something? That wave movement at the top I understand, but why does it move out at the bottom? How does the force applied move backwards from the direction that the string itself is travelling?
I'm sorry but I don't have a good answer for you at the moment. In my thinking, it shouldn't so I need to go back and take another look
+Bruce Yeany +L.Y. G. -- Touching the string changes the tension in the string loop. As it sounds like the sting completes about 3 loops per second, it should take about 1/3 second for a disturbance at the Launch End to propagate all the way around. Looks to me like it does.
_Hypothesis:_ Wave speed is proportional to string speed and loop tension. Repeat the experiment with Beaded Chain, which will allow longer loops due to less aerodynamic drag+more mass and momentum. Vary the loop length, observe time for disturbances to propagate. Look at video frame-by-frame to get more exact timings. [Note: it is also known as Ball Chain. See www.michaels.com/bead-landing-ball-chain-spool/10338105.html for example.]
so cooooool
I didn't see something as good as this for along time on you tube
you should try shooting paper airplanes! would be lots of fun and can test different styles of paper planes and airfoil!
good idea, I'll try that
Use brushless motors with ESC's and put some adjustable suspension on one or both of the wheels.
Ill do one of those this week, amazing idea Bruce, absolutly loved it.
Ah, so this is the famous string theory I keep hearing about.
collaboration with the slo mo guys would be epic!
It's not science until you make some predictions and test the hypotheses! Why does the wave not propagate as fast as the string does and why don't the waves go all the way around? Would they go all the way around if the curve at the far side would be less tight?
Totally agree.
atleast give/share some understand you learn from an experiment.
Instead of showing of something happening because its "cool" and then just say its science.
Setekh. Guys, this is not "string theory" in University. Its what kids get (as a little extra i imagine) in "science class".
Its the kind of motivator that leads some kids to be interested in the science behind it.
If you listen to some of this teachers other videos, you will see that he actually asks kids to predict what will happen if so-and-so is changed.
As usual I am not sure who has the most fun in your classes; you or the kids. However, If my basic understanding of physics is correct the string is being pulled through the wheels, not pushed. The resulting dynamics of the string is due to its inertia. I was always lead to believe that the only two pushing forces were gravitational and magnetic.
Just the same it is a fun machine that illustrates many properties of physics. Good job.
You are correct, the string is being pulled and it's continuing forward due to it's inertia. The old adage is pretty much true, you can't push string
i hope those batteries are rechargeable ones.
salame milan why
Why? Because of waste? If so, don't worry, this is an educational tool. It's most likely only used once a month or even once a year. Using rechargeable batteries wouldn't make much of a difference, just like with clocks and remote controls.
ronettreker But the waste is so negligible who cares?
Also, a lot of people don't know that alkaline batteries have a low self-discharge rate compared to rechargeable ones. A lithium Ion battery has the lowest self discharge compared to other rechargeable batteries. It loses 24% per year. An alkaline however loses only 3% per year. The champion is primary lithium which only loses 2% per year. That's why digital clocks can run for years using alkaline batteries
doesn't that allso mean that Li-ion batteries have the highest probable power output ? just asking not sure
Awesome video! I look forward to making one for my boys to play with. I can tell you make school amazing for your students. Thank you so much for that.
Good demonstration of longtitudinal and transverse waves.
У кого это появилось в рекомендациях после Крастера?
У всех
I love that little switch.
annyone noticed video lengt?
Bart N blaze it
Bruce your videos are awesome! Keep it up!
try cocktail tooth picks
+Art Connolly
I tried them but they hurt my cock.
So I tried them in my tail and that was painful too. Instructions unclear.
Wonderful. I really love complicated simple stuff that I think I can make.
video length: 4:20
😎
Brandon Szparagowski what do you mean? i dont get it?
blaze it
Liyeta R do you know what that means
Golden Thoughts smonk wed
1) Can you tilt the loop sideways?
2) Even with this device, you could not stop the wave. Do you think you can make an experiment were you can manage to stop it?
3) And this baffles me the most. On the slow moving "gravity assisted" version the downstream side of the loop seemed like solid. Why we observe here slow moving wave even on the downstream side?? I expected it to be at least as "solid" as on the vertical version.
woowooNeedsFaith
the "new" loop forms in the orientation that the string gets shot out at. if you try to move the launcher too abruptly you can tangle the in feed sometimes but that's about all.
You said "homemade" science at the beginning but u r in a lab... u destroyed my life.
Anyway, great video
mrchapman he could've been in a port-a-John and it still wouldn't have made a difference
all my videos are homemade, meaning all the pieces that are shown, I made at home,
Bruce Yeany it's a great video anyway hahaha
It could be fun to mix frequency in it. Fun to see the bending on th wire stay, did't expect it to stay.
Who is here after Steve moulds video?
Me! I’m surprised nobody else has.
I got a toy about 10 years back that does the same thing called a string thing with fancy UV lights. I still mess with it. Never gets old
more power and a metal string and we have a sword.
:O
Or a stringsaw
+ plasma arc we have light saber
what kind of engines are used in the gun? what is their power or rpm?
DC toy motors, 3 volt but running at 4.5 volt probably about 8,000 RPM unloaded
thank you very much for your answer Bruce Yeany
You could describe the physics of this system with.....
String theory
Finally! A real world application for string theory!
Nice idea, but the sound of those horrible brushed motors drives me crazy! Why don't people use brushless motors?
Because he built this with $10.
Nice experiment physics guy. Your channel is very interesting
thanks Chad
Time to build a flying chainsaw
this.................................... is......................................... AWESOME!!!!!!!!!!
I don't get it, what's the point of a string shooter? What's the science being taught?
does it matter? its something that you dont see everyday and its just something that messes with your mind when you first see it
Dude, we could totally turn this into a space elevator, just shoot a metal cable instead and pass some current through it, you can ride it out to space, it's awesome!
Javier Chiappa I think you're under thinking the requirements for such a task. First off, the power needed for such a feet would be through the roof. The string in the video is about 16 ft in length whereas the cable to reach an appropriate height would need to be about 70,000+ kilometres long. Don't forget you're trying to propel this thing into space from a single point of contact. Even if you could get this cable to create a loop large enough to reach a station in geo synchronous orbit, to utilise it would need to attach a container to the cable whilst its spinning going from 0 to a few thousand meters per second almost instantly, this would throw the cable off course possibly pulling it out of the sky. I could go on and maybe I will if you want me too which I doubt but I'm tired so maybe some other time
212superdude212 And one would have to factor in the fact the Earth's rotational forces and let's not even consider the forces of weather.
Sad we don't teach kids the math of physics. It's essentially the elevator cable problem.
We have built tall buildings but an elevator can not go from the ground floor to the top floor. Why? The diameter of the cable would have to be so large the wight of the just the cable needed would exceed the strength of cable and the cable would break.
This is a problem already exists in the tallest buildings in the world.
If we can't do it for a building not sure how it could be done to get into space.
You know what would be a good variation of this demonstration and turn it into an experiment? Have multiple string launchers and use different lengths of string, and strings of different diameters.
Great demo. And I can tell you love your job.
thanks, I do
If u turn it to its side u can put a paper airplane in it and it will shoot
Bruce, you're a good soccer player, golfer and bowler.
Brilliant! I have a similar device that propels a loop of chain. It exhibits wave behaviour too.
that sound awesome, I hope that you show it here on youtube
Absolutely fascinating, I'm going to have to try it. I'm finding this very reminiscent of technologies depicted in neal stephenson's Seveneves.
I really am loving your channel!
You have such great ideas!
i can watch it all day .
I really enjoy the Content you are putting out on your channel. I'm currently enrolled in my second level physics course at my state university. I really wish we had access to these type of demonstrations during lecture! It would make the study of physics much more interesting.
Wave motion, inertia, angular properties, momentum, and projectile motion can all be taught by this device.
Great work, keep it up. I'll show this to my professor and see if he likes your channel.
Sir, you are amazing, you definitely deserve much more subscribers.
found the part after @1:50 the most interesting: when touching the rope on the top it also simultaneously moved the bottom. More explanation on that would be nice.
Found this on a link from a recent Steve Mould video, nice work
this is my new favorite youtube channel! first video and an instant sub!
Thanks Ryan
Are there any practical applications besides fun? I simply can't think of any. There probably are that i have no idea about though.
I don't know of any but it is amusing
+Bruce Yeany (Yeany Science) it is indeed.
There's a concept called the "launch loop" that's being seriously considered as a future megaengineering project. Basically, it's one of these but with a circumference of 4000 kilometers that reaches up to an altitude of 80 km above the Earth's surface. It'd be a massive piece of maglev track suspended in the air by a heavy string spinning inside of it at 14 kilometers per second. This would allow us to build a normal electromagnetic mass driver floating 80 km in the air without using billions of metric tons of material to support it's massive weight. Essentially, this would enable us to launch things into a 500km circular orbit using only 120m/s of deltaV instead of the 10,000 to 14,000 m/s modern rockets use.
In fact, if the payload were allowed to accelerate past 3g (which is relatively comfortable for humans), it could be accelerated directly onto an interplanetary trajectory without using a single drop of fuel.
Sean James That would be sweet. But the cable would be crazy. We would need to have some exotic materials to have a cable like that strong enough. It'll be awesome to do so though.
Mr Rishi The Cookie
The cable could be made of modern materials easily. As long as it's accelerated up to speed at a modest rate, there'd be no seriously damaging force acting on any point of the cable that can't be damped out by servos. Damaging forces would be like the waves he created demonstrating this small version, except they'd be caused by gusts of wind, and servos could be used to cancel out such waves before they can do damage. A huge number of these servos would need to be disabled before cable failure would even be possible.
How were you able to get string to be in a continuous loop and have it look so seamless. is there a tiny knot I'm not seeing?
no knot. I used a small flame to melt the ends of the string and them stick them together while still hot. I wear leather gloves as I do them and roll the new joint between my thumb and finger to smooth it out.
Cool thanks, love your videos
Note to people who want to do this, you need to use synthetic string, not cotton, wool, etc.
I can think of no practical use for this, and I love it.
Well gee, now I know exactly what I'm making the grandkids for Christmas- thanks for the inspiration, Bruce! BTW, I just love your videos- so much science-y fun! :D
thanks Laura,
Sir, do you have to have 2 motors & if so, I guess because they are dc motors, you would need to wire them in opposite directions.
yes they are
if you had it coming from the other side you wouldn't have to wire it backwards though. wouldn't look as fancy i doubt.
is there anyway to try and read the wave length/form to tranlate to a fequency so it could be turned into an instrument???
super interested!!!
Well done Bruce.
Whoa! Looks amazing