Nuclear 101: How Nuclear Bombs Work Part 1/2
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- Опубліковано 28 вер 2024
- Lecture with Matthew Bunn, Associate Professor of Public Policy; Co-Principal Investigator, Project on Managing the Atom
Slides from the presentation are available here: belfercenter.or...
More information: belfercenter.or...
September 10, 2013
thanks for putting me on the NSA watchlist
MWB Gaming lol
Every American is on the NSA list. The Government is scared of us and collects all our data. Thank you Snowden. So if your hard drive crashes, just ask Obama for the back up. ;)
im not american im australian but i bet the NSA is still spying on me
also i think il have to purchase the backup from trump
obama would give it to me but trump would probably try to make me pay
MWB Gaming oh, Obama would make you pay, but TRUMP will make you pay with your daughter...
sorry for the bad joke if you actually HAVE a daughter....
lol no offense taken
trump would make me pay with both lol
Can you imagine going back in time to WWII and telling people "you know that super secret tech you're all working on? Yeah... we call this UA-cam"
I personally loved this lecture, and the lecturer did a fantastic job explaining everything, I spend hours a day watching and listening to lectures about nuclear physics and explosives etc because they interest me alot, I wish New Zealand universities would offer a degree or diploma in nuclear physics or pyrotechnics and explosives, or even an online course, if they did do this I would be there first student
+SuperBking1340 One method is to observe the path of a charged particle as it collides with a neutral particle.
SuperBking1340 Good question, I'm not entirely sure.
SuperBking1340 Now that I think about it more, using the mass of the two given particles and the angle of recoil from the charged particle, it could be determined what direction the neutral particle rebounded in.
+SuperBking1340 good question, but unfortunately I don't know the answer to that, you would need to ask the people that assemble nuclear weapons for the answer to that
+mark lister Im from new zealand too and really enjoyed this lecture
I'm building a bomb for my dad for his birthday and I want it to be big. However my yield seems to be consistently below the 50 kiloton mark even when I use enough material for a 100k or so bomb. I've got the hollow sphere and the air gap and the explosive lenses mostly dialled in, but still I end up with this figure "8" blast pattern that is not very optimal Can you please help? I only have enough fissile material for two more bombs so I can really have only one more test before I make the present.
Use the fissile material for the remaining 2 bombs for 1 bomb.
You've got enough material for a 100kt explosion? Is that assuming the impossible efficiency of 100%, are are you assuming maximum possible efficiency of 33, but only getting 16%?
16% is pretty good. Are you using uranium or plutonium? Boosted or unboosted? Reflected or unreflected? Tamped or untamped? How precise is your neutron injection timing?
Some speculate that the yield of a nuclear bomb is dictated by the by its position in celestial space. So, it may fizzle or it may go BOOM.
"All the energy and matter that has existed still exists. Matter does not create energy
of itself. The actions of matter enable energy to become manifest".
Interestingly you can enrich uranium using photo activated uranium salt decomposition. You’ll have to guess the salts that this would work with.
This approach relies on the minute differences in the chemical properties of 238 and 235. It only needs recrystallisation equipment.
It’s not an economically viable method though.
If I wasn't on a list from all the other cap I watch.....I definitely am now
some dude haha yup. I’m a Feynman fan so naturally this pops in my feed.
Great information, very informative. Lecture is off the chain, you know you are in the presence of a expert. On the other hand what horrible reality these devices have created. So sad and depressing. So much engineering in the wrong direction. One love y'all.
CVbeats to be fair more people wouldve died if they didnt bomb hiroshima and nagasaki vs an invasion of japan, the lesser of two evils if you will
Amazing video. Though obviously a very complex and chemistry / physics topic, professor Bunn does a fantastic job of explaining things clearly and in a simplified manner.
So I starting watching this a couple of days ago and heard him suggest The Making of the Atomic Bomb by Richard Rhodes. I finished it and yes it is a page turner. and yes it is very good. If you are interested in history of science you will enjoy this book. the book tells the history of nuclear physics not just an account of los alamos.
this vid just auto played when i was napping, just saying whomever might be spying on me lol
We hear about other countries who we don't want to have them, but the truth is the knowledge on how to is easily available, and is taught to students in school....yes even students from other countries no restrictions other than the general admission to the school.
I wonder what kind of informations in this video are intentionally placed misinformations.
But all in all, as far as i can evaluate that, a very good video. Thanks.
OpenGL4ever Sketches of the bomb structures are not correct. The explanation of the function is correct.
dieselscience
How do you know? Have you ever developed a nuclear bomb for a country?
Do you know what Y-12 is?
dieselscience
Now i know. But what is about you?
"But what is about you?" - If English is not your native language, that's OK but I don't understand what you are asking..
IIRC, the heavy metal Beryllium is used as the tamper.
Beryllium is not a heavy metal, it's the second lightest metal. Also it's not used as a tamper, but as a neutron scatterer.
Where can we download the blueprints for 3D printing?
That photograph at 2:20 is of the - Badger shot of Operation Upshot-Knothole in 1953 and NOT of the Trinity Test as Bunn suggests! Just look the pictures up yourself, if you don't believe me.
31:07 According to en.wikipedia.org/wiki/Thermonuclear_weapon#Compression_of_the_secondary
there are three proposed theories of how the energy is transferred to the secondary:
- radiation pressure exerted by the X-rays
- X-rays creating a plasma in the radiation case's filler (a polystyrene or "FOGBANK" plastic foam)
- Tamper/Pusher ablation
It's obviously not radiation pressure because that's a piss-weak effect compared to ablation pressure.
The x-rays cause the tamper surrounding the secondary spark plug to ablate so explosively that it causes a rocket effect. The tamper blasts cylindrically inward from all sides, compressing the spark plug to fission pressure + temperature. Ignition of the spark plug then pushes the tamper back out again, which kills the reaction before it even leaves the bomb casing. It happens so fast that they had to load the first H-bombs with paraffin to slow the neutrons from the primary down so they wouldn't reach the spark plug before it had compressed all the way.
Many thanks for the lecture though I cannot imagine a situation where I'd need that type of knowledge. :)
Thanks for the upload
This science made 1sec an eternity of time
Fission > fusion > fission > fusion > fission and in the end = huge boom and giant fireball and whole city gone in just one second.
Amazing. Its just amazing how smart are some people.
Great video. Great lecture. Is there a similar on nuclear power?
This lecturer is brilliant. I'd bet he could make "how paint dries" an interesting topic :) Thanks for the video Belfer Center.
Wouldn't plutonium 238 be great for nuclear powerplants since it generates heat and therefore be great in a steam turbine?
You're correct... Plutonium 238 is used as a heat source in very long-range exploring spacecraft (Voyager, etc). There's a special material that gives off electricity if one side is cold and the other hot, so one side is heated by the Pu -238, and the other side radiates heat off into outer space, at around 400 below zero F.
Fascinating! Thanks for the clear explanation.
Anyone familiar with the phenomena of the Ocean water around a Nuclear detonation turning temporarily black? .... I read about it years ago but am unable to find any info anywhere on the net, .... would greatly appreciate any help ... cheers
+getorfmalawn Its called a "slick". I think it does not actually turn black. When the hyper-sonic shock wave travels thru the water the surface becomes a little smoother thus not reflecting light as well. Right behind that shock wave is the one traveling slightly slower thru the air. Where the air wave meets the surface of the water it creates an effect call "cracking". It disturbs the surface of the "slick" and causes it to then appear white.
Cheers Tyler ...I since posting found the term "slick" mentioned in Wiki of all places .... Ive been thinking the phenomena is connected to the property of water to form a temporary "Lattice" through its H-bond network,... acting similar to a Black Body type absorber .....temporarily negating reflection ... you're explanation is not entirely excluded in that process, ( speculative as it is) with the tremendous energy compressing the molecules into forming the lattice .... interesting stuff thanks again for your reply mate
+getorfmalawn It looks like i spoke too soon on the "cracking" too. It appears that the cracking happens before the air pressure gets there. I assume the cracking is the result of the "slick energy" being released from the lattice as it decompresses. Can you expand on that?
Great video+speaker...even for an average IQ guy like me-
Just the fact that you underestimate yourself is a sign of a higher IQ. Plus I don't think average IQ blokes Care about this stuff. They are watching Britney Spears videos.
Not to mention look how many people have watched pt 1 vs pt 2. I bet most of the numbers who started pt1 never finished Pt1 let alone pt2.
Makes me wish i went to college... Great talk. Very interesting!
@39:38 are you referring to gamma ray detection only? If so, are you stating that cat litter emits a higher count rate (combined Th, U, and P) than *unshielded* enriched Uranium?
thanks for sharing this. very clear explanation and it was very useful for me to understand.
About 28:00 he says the core heats to "billions of degrees". Is this correct? I thought even fusion bombs don't get hotter than 40M degrees or so
Well, I guess he knows what he's talking about, he sure seems smart enough... But, it'd be kinda hard to measure, don't you think?
A Fission reaction is used to trigger a Fusion Reaction.
Yes, it happens for an extremely small period of time though.
Good question! Amazing how you get confident answers that don’t answer your question at all.
It’s ok to not know the answer folks.
Fissile cores do not reach billions of degrees. In kelvin, we're talk around tens of millions. Maybe 70 million max.
Was just looking for a short and sweet answer to fill my curiosity, like modern marvels. Good presentation though.
Interesting lecture. I always find it a little annoying when speakers have the quirk of continually saying "OK" after every sentence or two.
+Gray Bryan Mkay :) It's Mr. Mackey from southpark Mkay! :)
+BMFin still interesting stuff and a good lecture though :)
OK
The worst is when people answer a question by beginning with "So.."
This is a trend that seems to have exploded in recent years.
So what bothers you about it?
Critical Mass in the Critical Area...BOOM!
54:28 that looks like a soap bubble.
This shit crazy!,I got curios about nuclear bombs when I read unbroken.
This came up on my recommended list...
1:00:20 not precisely true. The US tested its weapons primarily in a desert. Under such condition you don't get a lot of fallout with an airburst. But there _was_ fallout in Hiroshima, an airburst, in the form of the "black rain". Fallout is certainly possible with an airburst if the humidity is high enough to form precipitation after the event.
It is true enough for real world purposes. Measurements in black rain areas indicate that doses could have been as high as 44 rads (0.44 Sv for gammas) at the top range of estimates. This is between nothing and fuck-all in terms of serious injury from radiation.
Modern nuclear weapons are larger. Most are in the few hundred kT range. Which gives a larger fireball that rises more rapidly, giving less, not more local fallout from an air burst.
I'm 15 minutes in, and realized , D.C. Current is relevant!
The graphite control rods in a reactor are what control the neutron reflections right? Pulling out the control rods causes the reaction to accelerate, while inserting them blocks the netrons, slowing the reaction? In the case of Chernobyl the control rods were all pulled out over accelerating the reaction, neutrons everywhere, then all control rods were quickly inserted back in, in a state of panic, but doing so caused the control rods to actually become reflectors, there were too many neutrons already about that, then excessive hydrogen gas was created, and thus only making the meltdown of the reactor, also explode. Can anyone comment on my understanding?
+SwingingChoke No. Graphite is a good moderator, better than water. Control rods are made of materials like cadmium and hafnium that have large cross sections for absorbing neutrons at desired energies. Inserting them blocks neutrons. Inserting graphite rods, which are not control rods, moderates the neutrons (slows them down without absorbing them), slow neutrons fission uranium-235 or Pu-239 more readily, which speeds up the reaction.
Chernobyl was a graphite-moderated reactor with light water cooling. Water is also a decent moderator a poor neutron absorber. If it ever gets hot enough that steam bubbles form in the reactor, neutrons zip across those steam bubbles and hit graphite, which is a better moderator than regular light water in that it doesn't absorb as many neutrons; that means, if it boils in the reactor, the reactivity increases. The water is operating as a "liquid control rod" that is never supposed to be removed.
Among the fission products, there are isotopes which absorb neutrons readily. The most important one of these is xenon-135. This isotope is a neutron-hungry monster. When you start a reactor up, there is no xenon-135 because it has all decayed. Over a few hours it will build up in the reactor, decreasing the reactivity. It reaches an equilibrium when it is being destroyed as fast as it is created.
In the Chernobyl reactor they had been operating at full power, creating a lot of iodine-135, which decays into xenon-135.
As they ramped the power down, they eventually had trouble maintaining the right level of reactivity because xenon-135 was being formed from decaying iodine-135 faster than they were burning it off, so they manually removed control rods to maintain the reactor to keep it running. Eventually the xenon-135 burned off, which increased reactivity, which increased power, which burned off xenon-135 faster, which increased reactivity. When they noticed the power unexpectedly and rapidly increasing; from low levels towards normal levels; they SCRAMed the reactor to shut it down.
The control rods were tipped with graphite, which is not a control rod, but prevents water from entering the channels were the control rods are withdrawn, giving even more control. The control rods had been withdrawn so far, manually, that water had entered these channels. The water is essentially acting like a weak, liquid control rod in these channels when present. As they insert the control rods graphite tip first to try to shut down the reaction, they push this water out of the channel with the graphite tip, replacing water with an excellent graphite moderator. This made the power increase rapidly far beyond what the reactor could take. Things overheated, broke, warped and they could not get the control rods more than about a third of the way in before they got stuck.
From mathematical simulation and witness accounts it is believed that the power was about 30 GW thermal when the first steam explosion happened (ten times normal; 3 GW thermal -> 1 GW electric), lifting a 2000 ton steel plate, and after that the excursion continued (less water) until the second more serious explosion dispersed the core so that it was no longer critical. The second explosion can have been caused by several different candidates, e.g. hydrogen from hot zirconium in steam, or hydrogen and carbon monoxide from hot graphite or prompt criticality, equaling about 10 tonnes of TNT in explosive force.
Thank you, I appreciate the clarification for me. I have a great understanding now.
Well that was interesting.
Very good video.
Well obviously he's wrong at 2:19 into the film. Took a slightly bigger ball of flames to whipe out the dinosaurs than we've ever seen since, but I digress...
l love i like this documental exelent job teacher
16:47. "They never bothered to test the Hiroshima bomb before using it because it was so obvious it would work."
HAHAHAHAHAHAHAHAHAHAHAHAHAHA !!!
NSA IS WATCHING.
tai hung Au well we are all fucked. Meh better know the truth....
"Gee, couldn't we figure out how to make a fusion bomb without the fission part? Nobody's ever figured out how to do that." Professor, what about Tsar Bomba, as tested on October 30, 1961 with a substitute of Lead for the U-238 tamper? Its total yield was 97% fusion. Do you not consider this to qualify? Not a challenge, just a genuine question.
If I was a terrorist, I would not try stealing nuclear material to make my own bomb, I would try stealing an already existing bomb. If I felt confident enough to steal nuclear material, I would feel confident enough to steal an existing bomb since I would have to deal with similar levels of security in both cases. And I would try stealing a Russian bomb, because their security measures have deteriorated a lot since the breakup of the USSR.
Your assuming that the people who would like to create a nuclear 'terrorist' event are outside of the government. Remember a few years ago when the US Air Force 'accidentally' flew six nuclear cruise missiles across the US? It is obvious which cruise missiles are nuclear and which are conventional. It would be like a group of people decide to take bananas with you on a hike, a second independent group verifies you have bananas and then you get to on the mountain you realize you brought your cat. That is what you have to believe if you think that was an accident, or it was a network of people inside our military/government trying to steal nuclear bombs.
actually its hilarious people think the security surrounding nuclear plants are actually secure, my friends dad worked there for years and always talked about he couldn't understand how bad things haven't happened already. due to security. just like the air ports when "9/11" happened they were saying we need security at airports, and im thinking uhh wasn't there ALREADY security there, who the hell is running this crap anyway? I swear everyday the human race isn't extinct is a wonder to me, because on a large scale human beings are greedy, manipulative, greedyx1,000,000, liars, egotist, self centered, narcissist. those are just the vast majority. WE NEED TO EVOLVE PEOPLE WAKE UP, burn your money and try working for something greater than yourself, the betterment of mankind.
***** The failure wasn't in identifying a missile as conventional instead of nuclear. The missile type involved in the incident only comes in a nuclear variant, and the missiles in question were supposed to have had their warheads removed. Basically, the missiles were left unattended for a bit and the guy who left them thought the guy who came after him had removed the warheads, and the guy who came after him thought the warheads had already been removed. Or something to that effect, I know I read a fair bit about the incident. The whole thing ended up costing pretty much every officer in the chain of command all the way up to the Air Force chief of staff their jobs, but IIRC not the ordnance techs involved. And no, it wouldn't have been "obvious", because the AGM-129 doesn't have any convenient windows to look through to see whether there's a warhead in there or not, the panel you have to open is inconvenient as heck and people were leaving it out of the checklists.
And you'd have to figure out how to arm the bomb. It's pretty difficult without a PAL configuration box, and those aren't available, even on eBay! :-)
And if you try a few random codes, you'll find out the bomb "defends" itself -- a small explosive inside ruins the primary's core, so the bomb is a paperweight until it's completely refurbished. These bombs are works of art internally, machined down to 1 micron, and if that gets screwed up, it won't work.
You'll also find out the "zipper", the neutron generator, and the D-T gas injectors have very precise timings.
A few generations of very smart people at Sandia Labs spent their careers developing ever-better PAL's ("Permissive Action Links"). I remember when Sandia was approaching college grads and asking if they would like to work in nano-technology.
There is a strong rumor we deliberately gave the USSR a PAL design because it was just a good idea for the USSR to have better control over their nuclear weapons.
I don't know the specifics and I don't want to get a security clearance so I can see this stuff.
David Small wanna bet???
So it sounds like just having Uranium-235 sitting around, it starts to break down? How do you contain it then without it automatically starting nuclear fission - or is that kinda the idea? Just thinking about the pellets used in fuel rods. Does the nuclear reaction automatically happen just by having it close together in pellets in the fuel rods, or do you have to have some catalyst to get it going?
If you are talking about nuclear fuel rods, that is a lot different from fuel for a bomb. Nuclear weapons have uranium enriched to close to 100%, while nuclear power plants are generally less than 5%. That means less fissionable U235, and is also the reason a reactor could never lead to a nuclear explosion.
Arnold maybe the reactor couldn't explode but there can still be fallout radiation for miles, also even tho reactor rods aren't the weapons grade choice , they can still be made into a crude / effective substitute. Which is what Mr. Harvard man said.
Just look carefully at the video.. All neutrons have to be captured by a U235 core and cause another fission.. Most will be leaking or not be captured..
And the powerplant also features control rods that absorb enough neutrons so that the chain reaction never goes logarithmic.
Jonas Carlsson
Yeah I get it for a powerplant, but what about in a bomb where you have a core of fuel sitting there? Seems like fission would spontaneously occur.
Watching this and repeatedly hearing about the astronomical orders of magnitude of heat and pressure that is released in these reactions, I wonder if we could harness this power to mimic the natural processes which create petroleum. Any thoughts about that?
Nice video
Im gonna build one at home
I find it interesting that a few Manhattan project physicist theorized before the first test that the chain reaction would not stop leading to the end of the planet.
So well done. Thanks for explaining things like we are not physics majors. I really hope people understand the need for the elimination of these weapons by the two superpowers who have about 10,000 nukes each and are ready to launch in 15 minutes at one man’s say so. No nukes!!!✌️☮️☢️
now we know.... wish we can make more useful usage of this stuffs.
I truly wish we had never concieved of such a device. I am very interested in them, but I understand that if another event happens, we may all be wiped off the surface of the planet. Total disarmament of all nuclear devices needs to come soon.
Anyone got some Uranium 325 laying around?? I'll even take plutonium 329 if that's all you have.... Keep this on the DL
WTS>Uranium 325 10kg = offer.. will accept zenny.
sorry bud. I sold it on Ebay last week. buyer came and collected
Andy's Coming Welcome to the NRC/IAEA watchlist.
lots of room here with all us ex members of the navy nuclear power program.
Yes, I have a few miligrams, but it's in ore form.
Is it wierd that this is just on UA-cam?
Amazing! :D
Man, get it right. Your first picture is completely wrong. That is not the Trinity test. That is a later test in Nevada. So I guess the Trinity picture wasn't stunning enough so you just substituted that? OK now you are saying a nuclear power plant needs a half a trainload of (?) per year. What are you talking about?
over 5k of muf is logged every year.
This lecture was very good. Equally as good is the lecture by Robert Muller from UC Berkeley who works in the lab where the scientists who had the idea for an atomic bombs taught and worked. ua-cam.com/video/5BHdsjo-NR4/v-deo.html
+Passed High School Physics The "idea for the atomic bomb" was generated in Europe. Rhodes cites the earliest glimmering about how a chain reaction might work coming from Leo Szilard, a friend of Einsteins, who had the idea in 1929 while walking in London. He went on the patent it without even knowing yet about the way in which it might be made to happen. The Americans only really got in gear when Bohr brought the news over of Haun/Strauss's splitting of the uranium atom in 1938, and the main sparkplugs were a mix of Europeans on the east coast and the team at Berkeley on the west.
puncheex2 What about Lise Meitner?
She was Otto Hahn's nuclear physicist (he was a chemist, and that explains why he was confused by barium showing up in uranium samples). She was driven from Germany to Copenhagen by Hitler's Jew shunning (her mother was Jewish) but Hahn trusted her insights and asked for them in a letter that described his experiments. And he got them, with whipped cream on top.
puncheex2 But wasn't she the one who figured it out that the Uranium atom was splitting into two large fragments with the release of energy?
Passed High School Physics Yes, indeed, she did. She i the one who performed the calculations that described the energy release in the transaction, after she realized that the barium-like stuff everyone was seeing really was barium, and what that meant. Sorry I didn't make that plain. She passed the word along to Bohr who took it to a US physics conference over the New Year weekend, and caused a lot of feverish cabling to labs all over the country immediately afterwards.
Stalin loved the book too....got a first run publication.
Making is so easy, just get material is kinda problematic,...
do u have to put atoms inside the orb or is it just space that has atoms in it. ie a metal orb with air inside surrounded by explosives.
One thing he got wrong - the core temperature is not billions of degrees, its between 10 and 20 million degrees
erbenton07 Actually no, the very core of a thermonuclear blast (in the very center of the fireball itself) temperatures can reach as high as 350 billion degrees Celsius, if only very briefly
in a pure fission device it's quite a bit lower, but still in the billions
the thing is, these temperatures are achieved so briefly that in just a few seconds it has spread out and dissipated to hundreds of thousands of degrees and in about an hour the atmosphere for a huge radius all around will have four digit temperatures
this is actually how nukes achieve a great deal of their kinetic blast energy (and is why they are known as barometric bombs) because such a high temperature in such a small volume of space causes the air all around to VERY rapidly expand in an effort to dissipate the heat, thereby creating a powerful shockwave
Hotter than the centre of the sun
Still disagree. Everything i find indicates only a few 10's of millions of degrees, not billions which is 1000's of millions. I can not find a single source that claims billions of degrees.
Here for example:
hypertextbook.com/facts/1999/SimonFung.shtml which cites 6 sources (scroll down a bit for the last source)
And here is another source taken from wikipedia:
The physical-damage mechanisms of a nuclear weapon (blast and thermal radiation) are identical to those of conventional explosives, but the energy produced by a nuclear explosive is millions of times more powerful per gram and the temperatures reached are briefly in the tens of millions of degrees.
In fissile cores, you're usually talking 50-70 million. In fusion plasmas, up to 350 million.
350 billion degrees? You mean 350 million. 350 billion would require an energy density of over 271 gigatons TNT equivalent per cubic meter.
my laptop camera is on wtf who spying on me.
I don't get the part where the guy is holding the plutonium in that case, without protective equipment. Why is that nuclear fuel different from what was released in Chernobyl? Please could someone explain.
Plutonium has a fairly long half life, and when it does decay, it releases alpha particles which are not penetrating. The the VAST majority of decay alphas will be absorbed before they reach the surface of the metal. Those that do escape will not even get through a person's skin. The primary Chernobyl nasty is the fission product Cesium 137, which emits a powerful gamma ray that will zap you, inside and out, from tens of feet away.
The picture is real and is of Sgt. Herbert M. Lehr holding the actual Trinity core in a small box. The magnesium box was to protect the precious core--not Sgt. Lehr. The core is not too radioactive to handle.
Raw weapons-grade plutonium is quite safe to be around because it is not very radioactive. The same is true of natural uranium metal and various grades of 235-enriched uranium made from it that could be used in weapons or reactors.
In other words, the kinds of plutonium and uranium that are used in weapons and in rectors are not so radioactive that you can't be around sub-critical samples of them safely.
That is true of plutonium or uranium that is going into weapons or reactors. Question: How are plutonium or uranium used in a reactors or bombs? Answer: Their atoms are being split (fissioned) into twice as many smaller atoms and great energy is released as these new atoms push apart from each other at fabulous speed. Problem: These smaller "daughter" atoms are often VERY radioactive and very dangerous to be around, even in small amounts. This is what is in the "fallout" from nuclear bombs that is so dangerous. It is the smaller atoms that the plutonium or uranium were split into that is so dangerous.
In a reactor, the atoms are split slowly over time and the small "daughter" atoms start to accumulate. These are just like fallout, but they are contained safely in the reactor rods UNLESS the thing blows up or melts down, etc. That is what happened at Chernobyl.
In other words, it is not the U235 or Pu239 that are so dangerous, but what they split into.
social effects of nuclear bombs.
isn't that the point?
what social effects, we are all dead! :D
Excellent lecture. But PLEASE stop saying "OK".
Damn to allllllll bombs
For anyone reading know I watched this but didn't understand anything.
I dunno. If I knew my lecture was going to be filmed and posted on youtube, I would seek out a shirt that wasn't three sizes too big.
I fear Mr Bunn will depart with the first brisk wind that happens by, and then where will the world be?
If you wanted to see the dude naked, just go during office hours like the rest of us. Otherwise, criticizing the mans clothes? Are you a reality show producer?
he is look like Louis c.k
I get to listen to a lecture from one of the most prestigious universities in the world for free, and I can pause and rewind it at my whim. Think about that for a second...!
Black SUV just pulled up next to my house.
I am a physicist and this is one of the clearest and well organised explanation to the layman and scientist on this topic - excellent presentation.
I am a chemist and this guy has no clue what is going on. Kinetic energy of fission products? Really? No mention of mass defect and the actual physics that is going on? This is disinformation pure and simple. I mean , he is an associate professor of public policy, associate! It shows. This man is in no way qualified to speak on this subject.
This professor is such a great speaker. Easy to understand even if you are not physics major.
kim was lit when his boys found this
What?..
Never though I would get the basic understanding, well taught, not locked in explaining in complicated terms at all, so well delivered. Was always wondering how they can be sooo powerful, now that guessing can rest :P
Why am I mesmerized by this deadly apocalyptic subject?
my father was at Castle Bravo in 1954.
Thanks James Cameron for an excellent 101 lecture.
No budget to steep, no sea to deep. That's who? It's him, James Cameron.
!?
Michael Corcoran Explains why his movies are loaded with bombs.
@Dan Kelly: It's a joke. Michael is saying Professor Bunn appears similar to James Cameron - and indeed there is a vague resemblance.
Dan Kelly:
A nuclear bomb took down the Titanic, and James Cameron attempted to tell the story with DiCaprio.
A good portion of this info was in my course of study for a power reactor operator's license. Nice refresher.
Why is the CIA following me
Dr. William Penney, the British scientist who developed the British nuclear weapons, had a permanent grin on. Look up a photo (any) of Dr. Penney and you can be sure he is flashing his toothy grin.
Maybe he was Stanley Kubrick's model for Dr. Strangelove. Penney was knighted for his contribution to the nuclear arms race.
so fascinating!!! i love learning about nuclear bombs!!
Gone fission...
Very good lecture. Easy to understand.The science to make it explode is well known. Not exactly top secret. The means to do it is the hard part.
I was looking at, like, a LEGO set for Nuclear Weapons on Amazon, but I couldn't find any. Do you think I'll have better luck on Craigs List?
56:35 Minor detail about hot air rising. I think he is mixing up cause and effect. You do not start with hot air rising and then colder air rushing in below to "prevent a vacuum". The hotter lighter air causes a lower pressure above the colder heavier air. This causes the cold air to be pushed up from its sides (as the side pressure around the cold air is higher than the pressure from above), which then in turn pushes the hot and lighter air upwards.
Think about an air bubble under water. Water on the top of the bubble flows down on its sides and fills up the bottom of the bubble. The permanent movement of water from the top to the bottom makes the air rise up. There is no water rushing in from below to fill up any vacuum.
Did they invite Iranian nuclear scientists and reps of the Guards of Islamic Revolution to this exciting lecture?
+Al Johnson Da.
No but your racism was
This level of understanding of the thermonuke is trivial. However, it was only arrived at after 40 years of experimentation and testing, which might lead you to the clue that a lot is unsaid here. Go read Clancy's "The Sum of All Fears" to put yourself to sleep.
+YELLING ARNOLD (IS EVERYWHERE) Got anything better than that?
eatenbytheweasel americans
Trinity Slide @ 2:15 is not a picture of Trinity, but a picture of Shot Badger from the Upshot-Knothole series in 1953.
well everyone who watches this is flagged by the NSA hahaha
mcdouches1 duh
I am watch this for education and I am in no way relate to ISIS. Life to America, Jesus Akbar!
PsuPepperoni that's actually pretty funny
mcdouches1 don't worry they are watching everyone, anyway!
Um , yeah, can I get quarter pounder of plutonium with tritium on the side. Hey babe, you want deuterium with that? Thats ok, I'll have whatever you're having...That'll be 13 billion dollars, pull up to the next window.
Fascinating. Great presentation.
I am just interested in how everything works together
Outstanding lecture.
If we could get to Pluto... We can get all the plutonium we'll ever need !!!💥💫🌐
and don't forget to watch the 1963 movie "Dr Strangelove, or ..." Still a great and important story.
I bet he's fun at party's