This puts every fancy diy to shame. If Im gonna make a vortex cannon this is it hands down

Great video! I arrived here after watching an old QI show where they did the same thing. I am teaching preschoolers English in China and this will be my new game! No more balls or sand-bags! The vortex-cannon will amaze their parents and the students alike~ Of course, I then watched all of your videos so far. Great job for all your videos~ Thank you very much. Please continue with the home-safe kind of experiments. Little students need them too~ All the best.

I've seen vortex generators with a piece of taut plastic/etc. stretched over what would be the back of your box. You can pull it back and release it to generate the pressure wave (instead of slapping the box), and put quite a bit more power in it. Great video!

Mount a subwoofer to it, put on a saw wave and enjoy your machinegun

Apologies if we have made ourselves sound like total douches in the process - we have been genuinely touched by the overwhelming positive response and attention and the only way we can show our appreciation is by giving you MORE VIDEOS! New one comes up on monday. It involves skateboards, how can that not be anything but awesome? :P

Really want this to get a million views! Love you Davs and George!

This is so amazing and simple! I foresee endless hours of fun with my smoke vortex cannon!

Futility at its finest in the first five seconds. Great video guys, keep up the good work!

Yes, the smoke just visualizes the path of the air so it looks better on camera.

@algarch - Great question! We didn't try any other sizes (we put our recycling out that week!) but we're going to go away and find out for you! Thank you for watching!

Yes it will work. The smoke is to show the movement of the air so it is easier to see.

This video isn't shared under creative commons. We hold the copyright and they havent asked permission to reupload it onto their own site and put ads around it to generate revenue. We are (for real) students who make these videos for the love of science and making people laugh, albeit in an awkward fashion. We were surprised as anyone that has notched up so many views, but we don't feel particularly comfortable that someone else is cashing in. We'd love to hear everyones opinions on this. :)

@algarch Hello again! Having done a bit of research we've found this out for you. If you make the aperture smaller, the ring will follow suit and shrink also. However, the smaller the hole the faster the air will rush out - this is known as the Bernoulli effect. If the air speed is too fast the ring will collapse immediately and we won't be able to knock over the cups at anywhere near the range of what we had in the video. :)

I'm going to go make one right now!! Super cool!!

Hello, it really is just that, a box with a hole in the front and something for it to knock over. When you hit the sides the compresses the air inside and forces it out as a vortex ring. Now, a vortex ring is a donut of air which rotates on itself. (Its not particularly clear from the video that it does that but trust us, it does.) These are quite stable and will only fall apart when it hits something more solid than it, such as an object or a strong gust of wind. Or if it lose momentum.

You guys have created fun times!

@URNScienceShow From such fantastic experiments, have you worked out an optimum box size / aperture diameter for maximum cup destruction at distance?

I can't wait to do this with my son! Thanks!

@FWshaun98 You don't even need the smoke :) All you need to do is reinforce the box on the sides you're not going to cut open then cut the aperture. We only used the smoke to make the air flow visible.

This is the easiest way to make one. Thanks for sharing. Will give it a try.

For anyone who's going to make this thing, here are few improvements you can: 1. make a 2cm radius hole instead that large one shown in video 2. connect a used up toilet paper roll cardboard onto the board for increased accuracy 3. ??? 4. profit!

"Secondly, put a hole in the box." I know where this is going...

if there was a way to make it silent -> great halloween tricks

It depends on the size of the box! You might have to experiment a bit.

I'll try making one of these with my nephews this weekend.

FANTASTIC!

That is immense, guys. I know how I'm going to be spending my weekend. :-)

@Lighningbreaker It's only to make it visible, removing the smoke allows for stealth attacks.

did this at the weekend its well cool

When I make one of these I'm going to add an overhang over the hole so that smoke doesn't block my line of sight.

@Lighningbreaker The smoke is only there to make it visible :) It will work with or without smoke!

I assume that the vortex would be smaller if you cut a smaller aperture in the box. But what would that do to the range and intensity? Did you try any others prototypes before this one?

must make one now!!!

Of course, it works just the same. The smoke just makes it visible and so much cooler to look at ;)

Cool!!!! What's the smoke machine? Pls answer...

This is... actually... pretty... fuckin' awesome.

Does it work without the smoke in? :) I mean, the smoke is quite dense and would pack a punch on those cups, but does atmospheric air also knock cups out?

Cool! How did they generate the smoke?

I wish my science class was this cool

Can you increase the power by making the hole smaller?

@URNScienceShow Hi, is there a specific ratio to the size of the aperture to dimensions of the box?

Cool. I assume this is a similar phenomenon to those ring bubble videos people with underwater GoPro cameras are fond of making.

that was AWESOME!

Very cool!

Do you all have any how to on constructing a vortex cannon? I would really like to try this if it is something that is able to be done with things that are available to everyone.

Will that work if I cut hole smaller so i can get bigger range ?

Very cool indeed

With the aim of a Storm Trooper O.o

Please explain this from fluid mechanics aspect. Angular momentum conservation?

Much Enjoyed!

Alas, they do. I was shocked too.

Is the smoke only there to make it visible or do you need the smoke so that it will function?

The Thundergun is finally explained. Another thing added to ma bucketlist (Make a cannon with the same effects as the Thundergun).

will it go further if the hole is smaller?

Have you tried different box sizes and different hole sizes and shapes?

When you started the steps I wanted to laugh. 1st get a box, 2nd put a hole in the box. Damn SNL for that song.

We get it, you vape

out of curiosity, if the diameter of the exit hole is smaller, but the same volume of air passed through, would it be as powerful/travel as far?

I had the same train of though. I was half expecting him to tell us step 3, put your junk in the box.

is adding smoke really necessary for the pushing effect?

George gave me a tour on the Nottingham open day!

Yeah you can pick similar things up from shops, but making your own is more fun we think!

Oh with that u can practice "panchira" (upskirt ) but in japan there's natural vortex doing panchira everywhere

so my nephew had a science fair project this spring break and i was thinking of using this. is this all i really need? I tried to find on your website the explanation of this but could not find it. @URNScienceShow

Can you guys show the video how to make it

Does there HAVE to be smoke of some sort, or was that just so you could see it happening?

this is so cool omg

Wow it works! :) did the same with my son right after seen that. BTW, does anyone knows how to make safe smoke at home?

This is great fun.

wow! old news is so exciting!

You can indeed! It's like having an elephant blow at you! Pretty cool as you can't see the ring if you don't add smoke so it surprises you too!

Yes. Any smoke or powder-like substance will work fine. Have fun!

Awesome, now I know what I'm going today.

Is the smoke really necessary?!? I really wanna try it.

freakin awesome

Would it work without smoke?

Will it work without smoke?

Cheerio mate. Nice cannon.

Very good

My girl, daughter and I found a box 65x65x85cm. We made the hole 15cm of diameter. We don't have smoke machine, so, we can't see the vortex. But it works... tumbling some cups... and moving our doughter hair. It works with a 4m distance. We tried larger, but, as we don't see the vortex, it behaves strange... The question is: should we make the hole bigger? I think there would be a math to generate the best hole for that dimensions... do you know it? If not... do you have any suggestion? Thx!

Does it need the smoke or is it just there to help guide you?

IT JuSt AweSoMe ....

Is the smoke necessary or was it only for visual effect?

OMG I have a fog machine too! I'ma go make one of these.

Tuesday is your day in the box.

What did you put into the box ? Air ?

Now, what happens if you get two, and let the shots hit each other in mid air? Would maybe look cool, especially if you could get two different sized ones maybe...

MANUAL DO MUNDOOOOOOOOOOOOOO!

As you build you have used??

HA HA. Yes exactly what I thought of when I saw it. The fact that I am not the only one makes my day.

what is the hole was a triangle or skware or so

oi lads whats the benefit or a point of this smoke gun? what could it be used for ?

was it just me or when the dude said "...we have to put a hole in the box" the next line in my head was "two, put you junk in that box, three make her open the box."

is the smoke required?

Is it possible to make a vortex shotgun with multiple smaller holes?

"You can get it from all good forest fires, but I get mine from Sainsbury's." Beardyman reference, anyone? :D

It can indeed! We just used smoke to make the rings visible.

What on earth do 31 people have to dislike about this? It's just so cool. lol

what would happen if u made a smaller hole and copress the air more and make it more powerful

Thanks guys cool.