6:19 are we just ignoring the fact that the ball fell into that tiny hole?

"this needed to be aimed perfectly so i eyeballed it"

Imagine how weird it would feel having a magnetic sledgehammer and trying to hit a copper wall

That’s so awesome that you said “ I’m not putting a back stop up because I’m SURE it won’t go through “ and you didn’t edit it out and kept it. We learned together 😂. I’ll subscribe.

Use compressed air to shoot your magnet. You can make it go slower so hopefully you can see some sort of change. Also I know if you heat up a magnet it looses its magnetic properties until it cools down and then doesn't come back quite as strong. So maybe the powder is getting the magnet hot which isn't good. Also if you can find thicker walled copper pipe that should help. Keep up the good work! Oh and if I am looking at this incorrectly please let me know. I never claimed to be an expert. ;-)

I'm 64 and these things are still interesting to me. In 1982 neodymium magnets were discovered. It's only a matter of time before we visit our neighbors in the galaxy. I'll be dead but our children may know our neighbors. Educational entertainment and fun. What more can you want from a You Tube video ! Thanks. S

4:30 Warranty void, if used as a cannon recoil dampener.

In the Machinist world we use soapy water in a spray bottle when drilling acrylic.

Well if I'm ever accosted by someone with a bunch of tiny magnetic pendulums, I know how to defend myself.

I'd love to see someone shoot a magnet through a coil and record the current produced with a scope

6:19 that magnet goes STRAIGHT INTO THE HOLE in the table. r/nevertellmetheodds

You should revisit this using compressed air rather than combustion. IDK that there is enough heat from the cannon to demagnetize the magnets but its a possibility I suppose. Might be worth trying again to see if there is any difference, and you wont have to worry about the smoke.

How about shooting a solid copper or even silver projectile through the field of an extremely strong electromagnet? The setup would be quite simple as you'd only need a rifle for which you can find solid copper bullets, some pvc pipe, some welding cable and a bunch of car batteries. Ideally you'd also have to come up with a way to fire up the magnet just for a second or so while the projectile is being fired. That way you don't melt your cables quite as fast.

I would suppose that a spherical magnet would quickly rotate into an orientation where it was doing least work, once it begins to induce and experience the opposing magnetic field. (This of course would reduce the slowing/stopping ability of the copper.) Have you noticed spherical magnets slowing down not as well as cylindrical magnets when dropped through appropriately sized copper tubes/pipes? Thanks!

well, idk where you saw the magnet coming through there, but ok.

Why not use a copper projectile and use the magnets to induce the field in the bullet, to avoid de-magnetization from the heat/pressure of the cannon blast?

11:00 Am I the only one that cannot even see the cannon ball when it was answered conclusively??

It would be interesting to see you shoot a magnet through a coil of wire with lots of turns to see how high of a voltage spike is produced from the rapid magnetic field changing. Could generate a spark if it is high enough!

Great video! I just found your channel today and have already spent a couple of hours watching and learning! Thanks for your information and science experiments!

You look like a young version of Ted Cruz. Or the current version of Ted Cruz came from the future after you invented time travel.

I'd like to see the voltage generated by the projectile when gently dropped down the tube vs shot. In other words is the inductance proportional to the velocity.

Magnets lose their field when heated or thrown into something solid, so your magnet could've lost its field after some shooting.

Thanks for the video demonstration and the experimental concept. Keep up the good work!

Very cool. Subscribed. TY. I loved the last slo-mo clip you could see the shockwave sparks come out first

It would be cool if you place a 45 degree mirror on the axis of copper tube and image the magnate moving inside the tube with the high speed camera.

I really like the fact that even though the outcome was not what you intended you still posted the video... That Good science man 👍

Very cool video man! This is exactly the type of videos I enjoy. Thank you for your hard work!

Maybe try shooting with compressed air I know it's not how a traditional bullet is fired but I think it may slow it much better

Always a good day when Nighthawk uploads a video!

The effects of inductance is an exponential, the closer the receiver, the more power is transferred, with the exception of tuned circuits which amplify inductance effects (but which are likely still an exponential function on a larger scale.) TL;DR, the closer the plate is to the magnet, the more its effects are felt.

One of my thoughts is the gap between the copper and the magnetic canonball is to large to really have much affect. When you demonstrated the magnetic falling through copper tubing the gap between the two is pretty small. On the pendulum demonstration it didn't cushion the swing until the magnetic was quite close to the copper. Even if you where able to able to reduce the gap with the cannonball demo, I think the magnetic field of the cannonball is just to weak to overcome the kinetic energy of the cannonball. It was interesting to see and I very much appreciated you taking the time to do this. Thanks !!!

Great experiments, shows great results. Congrats!!!

Some channels use way more expensive cameras, others tens of thousands of dollars cameras but this channels still has the most appealing result I've seen yet. The image is eye candy. I don't know why, something with the black levels or the contrast.

The plates act like a pipe with a slit, or like a coil that isn't short-circuited, making them not as effective. However, the amount of stopping force copper has varies proportional to the speed, whereas the bullet's energy with the square of the speed. So, if we increase the speed of the bullet 5 times, we increase the stopping force of the copper also by 5 times. But the bullet's energy increases 25 times, making it easier to push through. Would be interesting to shoot the bullet through a coil and see how much power is generated and "taken away" from the bullet.

Something similar to this has been proposed in another comment, but it would be cool if you repeated the double plate experiment but attached an oscilloscope to measure the voltage between the plates. Not sure is you would need to have a conductive connection between them or not though. And you might want to use a magnetic projectile that will maintain its orientation (somewhat) while in flight, if that's at all possible. Maybe by using a non-magnetic slug of some kind designed to be passively stable (check out Taofledermaus' channel for some good examples of passively stable slug designs that don't need rifling) and then attach magnets to it somehow so the magnetic field isn't tumbling through the air as it would with the spherical magnets.

Your choice in the fuse vent placement is actually quite fortuitous. Attach a laser pointer, centered to the fuse vent. I’m sure results will be far better than simply eyeball’n it. Thanks, your efforts are most appreciated!

Could you try to show the magnetic fields occurring in the next video ? I'm thinking metal shavings - spread some on a sheet of paper far enough away from the magnet (maybe a think copper plate) so they will only move due to the effect. Sorry for my English, I hope you understand what I mean.

I made my own eddy current brake dynamometer and found that there was indeed a certain rpm where the torque maxed out and then started to go down with further increases in relative speed. I've also observed this effect when an induction motor starts up. At first the slip frequency is 100% and torque is quite low. You can hear the slip tone from the motor. Then as the motor speed increases and the slip frequency drops, at some point, all of a sudden the motor takes off and accelerates rather quickly to full speed. This explains why motors have a break down torque, otherwise torque would just keep getting higher and higher as the motor is slowed more and more by the load. It also explains why rotor bars are carefully given a particular cross sectional shape to produce the desired torque curve. I used to think that lower resistance would make for more current and more force as relative speed goes up, and it does up to a point, but it is a curve that goes up and then back down. What I learned is that the copper pipe effectively gets thinner walled as the speed increases. At some point this thinner wall makes the current go down and the force goes down with it. For my dynamometer the maximum torque was at a relative velocity of about 19 meters per second, the speed where the disk passed under the magnets. I was using an aluminum disk. It dissipated 5,600 watts of heat, or about 7.5 horse power.

Your design for the cannon was the first time I've ever even considered the fuse placement. Now that I have, you make me wondered if the cannon has the fuse where the powder chamber and the projectile met, thus allowing for a more consistent burn off. The way yours is causes the exothermic process to begin at the back, and probably resulting in premature discharge, blowing powder out before ignition. Not that yours was insufficient for the experiment, thanks for that! I've often watched your videos and enjoyed the content.

Thanks for answering the question with a hands on experiment

I was looking for an experience like this for a long time. Finally, thank you for doing it, thumps up for you.

You should take a long coil or just a single turn. and fire the magnet through it. Put a shunt resistor of known value in the coil and trigger an oscilloscope on the rising edge of the pulse. It would be cool to see how much energy you can get out of the setup.

I really appreciate your efforts ❤️

If you ever revisit this a cylinder shaped magnet might insure that the projectile doesn't spin in the direction of the induced field. Thanks for the vids. I love your channel

i submit that the field in your ball magnet is tumbling around randomly reducing its efficiency. perhaps a rifled (spinning) magnet with the field oriented along its length would work better in your copper pipe.

A) I saw a YT video where the person who machined a piece of acrylic took a torch to smooth out the inside of the machined acrylic. I can't remember exactly who that was, maybe "Hydraulic Press Channel"'s "Beyond The Press". It didn't make the acrylic perfectly see through, but it did remove the cloudy effect & just made the machined area blurry. B) Another Great Video NHIL THANK YOU !!

How on Earth is that possible to have 10% dislike on this video? Is it because the copper pipe didn't work? It was a perfectly executed experiment based on a premise some hoped it will solve the bulletproof theory they have imagined. You've just proved them (or even yourself) wrong. That is exactly what stands between theory and experimental knowledge. Great job!

Thank you for this fascinating demonstration!

Great work man, this must have been a frustrating experiment to film!

What about using a powered copper coil to induce a magnetic field? Almost like a coil gun but in reverse.

I was watching magnets melt metal with my brother and this question came to my mind. Glad to see that a video already exists to answer my question!

Nice experiment, thanks for making this video.

This is amazing!!!

To cut or drill acrylic you should always sprinkle water. Some people almost soak the acrylic. Try next time.

Will a huge magnet stop a copper bullet?

Wow! Thank you for going through the painful process of doing this. Man, I remember watching you do outdoor stuff back in the day! Thank you!

Very cool experiment, thanks for sharing! Leaves me with lots of thoughts on the many variables... how would differently shaped magnets (spheres, cubes, cones, etc), a rifled barrel (meaning the bullet and it’s magnetic field were revolving), a coiled copper pipe, etc affect the test! Your videos are always very thought provoking!

Now to figure how to do the same against non-magnetic projectiles. For now, exploring theoretical force fields will suffice. Wonder if changing the shape and geometry of the copper will produce a stronger effect? Or using something even more conductive?

Could you do the experiment with a copper disk like at the beginning of this video but cut a slot going down to a hole in the center so your pendulum magnet can swing through will it stop like if the disk was whole it would be a better visual than the Canon I believe

I think it would be really interesting to see the operation of different powder chamber designs (particularly in slow-motion) with that see-through acrylic. Many early guns and cannons had bell shaped breeches, reduced diameter breeches, or both, to increase performance. Nock's patent breech is another interesting one, utilising an anti-chamber increase ignition speed of the main chamber.

Fantastic channel!

"I'm probably going to put a hole in my barn door if this doesn't work"... AHAHAHAHA

very interesting proof of concept. thank you for sharing

sir, instead of firing what would be the result if its been sling shot or been projected in some other kind? because the heat produced from the firing may cause the magnetic to loose its power right??

There is no significant slowdown because there is a finite "optimal speed" of magnet vs copper to produce maximum "stopping force". Too slow and too fast relative movement will produce "less then optimal" forces. This fact is well known when designing induction motors: the typical torque curve as a function of slip has optimum, and decreases if we deverge from this optimum.

Get a clear filter to protect your lens. Cheaper to replace :)

Love this channel!

Excellent presentation, Ben! Tesla..! I've read two books about this amazing man...

This ideea is very usefull if one wants to slow fast a plumbob tracer that has a significant tracing length (elevator rail tracing during montage) we also use water (cheap method) or oil immersion of the weight (better then water) interesting video :)

"You're real smart, aren't you, college boy? Think you're smarter than a bullet?" - Emil

New subscriber...i appreciate your video..pretty cool stuff...i love science...

REally appreciate your work and responsiveness. In your introduction i heard you say the question was: "can a magnetic field catch/stop a bullet? Which you turned into "Can a magnet stop itself? The preferred experiment would be to use an electromagnetic field to induce a reverse magnetic field in a passing bullet, if possible. (maybe with a ferromagnetic bullet) And a clarification in the theory, which is flawed by evidence of the paradoxes of EM induction (see wikipedia). Also, by altering the direction of an electron beam, one can demonstrate that not all moving charges generate magnetic fields, The magnetic fields are generated by charges that are aligned by external charge fields. Wires with current generate magnetic fields because the aligning field is positioned end to end within the conductor. With that condition, the current then is proportional to the number of charges that are where the current is being measured (the magnetic field is proportional to the currrent with this distinction. With this distinction, one can imagine that magnetic cores amplify the magnetism of inductors by virtue of adding a masssive number of charges that will comply to the orientation of the charge field of the loops of conductors; explaining why current amplification in transformers is proportional to the number of turns of coils. It may help optimize the design of your inductor bullet trap, keeping this in mind (maximize the coils, use high voltage (current is a nonsequitor (might play with this, but expect little influence, add a ferromagnetic core material and if DC does not stop it, try pulsing DC at a high frequency (with a compliant ferrite HF core, but giving the bullet multiple hits in the trap, an alternating voltage might make the bullet tumble and deflect more than slow it). Note: There are designs similar to this that "wiggle" laser beams, if memory serves. If photons were bullets, in principle a wiggle is a soft stop... so we know this is possible. Another aspect of this is the opportunity to clarify the process of EM induction. Note, an electric motor with an inductor winding that has capacitance (like a bifilar coil with the start of the primary winding connected to the midpoint of the 2nd parallel winding will capture the magnetic field in the capacitance, which shifts the dominating polarization of the charges along the winding until that charge is transferred to the coils themselves, which in an alternating magnetic field, synchronizes the "Lenz" effect in reverse of a normal induction field in a purely inductive coil. This amplifies the total electricity picked up by the conductor as it self-induces power in synch with the incoming magnetic field. It also puts the fields in opposition, not attraction, but in a boosting mode. Which means it would accelerate a passing bullet because of the delayed Lenz effect(not what you're looking for. (Thane C. Heins has many videos on this application which was patented back in th 1800's, the effect was reinvented by Joe Newman (see his Big Eureka motor) Joe did it with very long coil runs (miles long, enabling him to commutate the voltage impulse before it left the coil; even at light speed the charge field in a conductor 7 miles long takes ms), and ran his motor on dead batteries (just voltage created the driving magnetic fields), current does not create the fields, it just heats the conductors.

Can you measure the electric changes in the copper while the magnet interaction?

When I read the title, I thought "Some dude made a railgun at home", but then I read the comments and realized "Nope just the exact opposite of a railgun because you're trying to stop a projectile using magnets instead of accelerating an object using magnets".

Amazing video, thanks for making it

Nice reasearch done I appreciated ur experinent

"Oncoming magnetic fields are sooo exciting!" - electron

You just need to reduce the drill speed in plastics to prevent it from melting.

I know someone who works at a large amusement park. He told me the rollercoaster uses magnets to slow the cars at the end of the ride before the brake stops the ride. I believe the magnets are using the eddy currents to produce the opposing magnetic field to slow the ride without the need for power or some mechanism. Also it saves wear and tear on the final braking mechanism.

Myth busters! This kind of video hits my nostalgia really hard.

If a bullet won't be stopped, then you could run a controlled experiment to see at what velocity a projectile could be stopped. Future video maybe?

1:32 *Momentum is not converted to energy!* Momentum is conserved and energy is conserved. The momentum is transferred to the Earth. The momentum balance is not necessarily intuitive since we don't observe the transfer of momentum to the Earth (nor do we notice the original transfer of momentum from the Earth to the magnet. The kinetic energy gets converted to electrical energy and then to heat (energy tends to end up as heat one way or another). This may seem like a nit picky comment but the conservation of momentum is a non-trivial part of physics.

Man good on you for doing the experiment

Funny that KZfaq recommended me the first video and I watched it, had the same question after the video, looked for an answer for the question and found this video.

This guy made a 12 minute video feel like 5 minutes great video 👍

If you had a giant copper tube and a large magnetic platform to stand on could you slap that tube on the outside of a high rise building and slide down the tube as an emergency escape? Just spit balling here. Seems like that is what is demonstrated in a small tube. Certainly the economies of scale for a giant copper tube would negate a benefit but it seems like it might work.

Great experiment. You can also water-cool your bit then you could drill the hole in one go.

Incredible love your videos and you explain so even I can understand. 👍

There must be a mathematical formula involving the mass of the copper, the momentum of the projectile (speed times mass) and the magnetic strength of the projectile; oh yeah, and the temperature of the copper.

your eyebrow movement is very coordinated

haha awesome demonstration of lenz law! :D, much better that the old "magnet falling slowly through a copper pipe"-trick ;)

What a wonderful experiment! Thanks for sharing it. I wonder if a fast moving magnet can effectively become "supermagnetic" in the same way as ab object can become supersonic. So, the magnet is travelling faster than the induced magnetic field can form in a conductor with that particular inductance. If there was a way to see the magnetic fields we might see similar images to those of supersonic jets in air with shock waves and cones etc.

You might not be able to stop a bullet but I bet you could use an armoured plate with extra magnetism to deflect a slower round. Bullets are around 3000feet per second whilst anti tank projectiles are around 450 to 500 feet per second. Deflection combined with cage armour might do the trick better than cage armour alone.Nice presentation.

you need a superconductor i reckon. that should do the job. go talk to ben krasnow of applied science!

Chicago and Houston needs this

add a farraday cage in sections were also discussed back in the day and of course followed through on to achieve affect for film and improve bullet proof glass making it obsolete in certain instances. The tunnels in star wars films are often magnetic chambers that can stop all metal from entering. Thanks for the video it was really interesting.

My father was a mechanical technician for Eastman Kodak for over 30 years. His job was to take the blue prints given him from the engineers and built it into a working model of whatever it was. One thing that he was supposed to build needed stiff but spongy urethane foam for shock mounts between the case and the piece of equipment inside it. Several people tried razor blades and exacto knives with varying shaped blades. The engineer demanded EVERYTHING to be neat and professional looking. My father took several pieces of the foam to a different part of the plant where they used liquid nitrogen. He dipped the foam in the liquid nitrogen and quickly ran it over to a drill press in the shop and made perfect holes. He aggravated the hell out of the engineer that designed it because this engineer had it in for my father. He never did find out how he did it. :)

I think the problem here is the shape of the bullet, not the principle theory. When the magnetic bullet enters the copper area, the magnetic field can be aligned any number of ways. For the inductance to have full effect, it needs to be perfectly aligned with one pole of the magnet going forward, the other going back. The effect will be completely gone, if the poles point to the sides or if they point upwards and downwards. What's more, the bullet will turn around inside the copper even if it is perfectly aligned, because of the inductance. This will help it reduce the force of the induced magnetic field on it. And once it's aligned away from its flight direction and points up/down or sideways again, the inductance effect will be gone. This would also happen with a smaller magnet when you drop it through a copper pipe. It's why the magnets used for that particular experiment often fit exactly into the pipe, they simply can't turn around. So you might want to try this again, first by dropping the bullet magnet through the copper pipe and see if the same none-slowing effect appears, then maybe get another shape of bullet, one that won't be able to turn around when it enters the copper pipe.

Like the larger magnet through the copper pipe, what if you used a pipe that was only slightly larger diameter than the magnetic ball? Would that have any affect on the magnetic strength output?

2nd shot at the sandbag moved impact point to the left, as the 1st one had no ice!