ABCs of Radiation

[@hycron1234]

If this guy had been my teacher in school, I would never want to stop learning from him.

[@woodsplitter3274]

Yup. I wish that I had better chemistry teachers in hs. I wish I was a better student in the classes, though.

[@edwardbaker5373]

I could watch this man all day. Wonderful speaker and presenter

[@doit9854]

My favorite part is that he's using Mirror-writing so that we, the viewer, can see the proper orientation of the text.

[@notinterested8452]

He's like Homer, Homer Simpson.

[@HappyFlapps]

And SOOOO damn sexy too

[@rustyshackelford4613]

I find it funny how i was always bored on alchemy and physics and never payed attention but here i am years later watching this man . Turns out that most professors cant really make you interested in such subjects

[@doit9854]

@Dick Fageroni you must drive a taxi in the uk cause your talking on the wrong side of the road homie.

[@philipgates988]

As a former teacher I am envious of this mans calm and entertaining disposition.

[@SeattleSandro]

Ditto. I taught science for a bit and I never had this calmness...granted, I taught 7th graders, so perhaps that was never going to keep me calm.

[@campbellrafuse7960]

A truly blessed world to have this type of education for free on the internet

[@AltereggoLol1]

"Anyway, lead will _eventually_ stop it!" is a great catchphrase for a nuclear engineer :D

[@benjaminbenavidesiglesias52]

I loved :'eventually'

[@nathandanner4030]

Also lots of concrete.

[@souslicer]

That cobalt 60 real close to his balls

[@bigbuilder10]

@ Lead won't go through skin, wash your hands before eating and you'll be fine. Reason lead paint is bad isn't because the flakes of paint touch your skin but because you could accidentally eat some. Lead is still used in roofing around pipes, larger mansions and other big buildings use it as the roofing material (instead of shingles and tar) because it's easy to work with and don't need much to cover a surface.

[@bigbuilder10]

@ I am me and know that lead (being the large element it is) is unable to be absorbed through skin. Only through eating, and technically breathing in lead particles, can it enter the body.

[@ME-rd4so]

I am impressed by his ability to write backwards.

[@General8675]

ME it’s a reflection of the original video. He right handed as you can see from The demonstration.

[@philrogers4535]

They flip the video left to right.

[@antuans1473]

@@mrsnoop1820 look at his watch writing and at the demos

[@Charlesincharge42]

Flipping the video is one way, but if you want to learn to write backwards, the easiest way is to start writing with your non dominant hand, the way our brains are wired, it will be difficult not to write backwards. It will look like kindergarten writing at first. If you can master writing forwards with your non dominant hand, you have rewired your brain enough to write backwards with your dominant hand. So a few options.

[@philrogers4535]

The buttons on his jacket are on the wrong side. So is he writing backwards or is the video flipped?

[@elijahsdad]

Me: It's 2 am, I'm going to sleep: KZbin: Want to learn about the ABCs of radiation? Me:

[@TacoTacoTacocat]

Guess whos up at 0030 learning the ABCs of radiation lmao

[@ScarletFlames1]

5:17 AM here, plz halp

[@nolanhanson5743]

2:25

[@samirbouhdiba7742]

same here

[@hycron1234]

There is always time for greater understanding.

[@michaelkrusche1760]

As formerly trained nuclear physicist I like how things are presented. Great job.

[@vikinglord7545]

Do you mean formerly or formally?

[@michaelkrusche1760]

Viking Lord I meant I got my degree in nuclear physics long time ago.

[@andrewbellinger6120]

Shouldn't it be the abg's of radiation?

[@uploadJ]

I C what U did there; cute.

[@suspiciousobjectiveobserve8083]

Arterial Blood Gas 😉

[@baruchben-david4196]

Or t8alpha, beta, gammas...

[@gyrgrls]

@@uploadJ ICURAQTπ2

[@gyrgrls]

@@suspiciousobjectiveobserve8083Those smart. I prefer roman numeral 4.

[@TheConjurersTower]

"Don't eat radioactive cookies" ~ Nuclear Professor Guy 2019

[@許進曾]

I heard another version of this. It reads that you have 3 cube one emit alpha ray, one emit beta ray and one emit Gama ray. You can throw one away but you have to put one in your pocket and one on your hand the answer rather different it says you put the block with alpha ray on your hand because it can be stop by tour skin tissue, then you put the beta cube in your pocket because your clothes and your skin will at least absorb some of the beta ray and the Gama one would be thrown away because nothing can stop the radiation harming your body. However the author says if possible throw all three away.

[@bobbun9630]

Of course, the major source of radioactivity in your average cookie is probably potassium 40, which is a beta emitter...

[@ironcito1101]

@@許進曾 Betas won't be stopped by your skin, and even if they were, that is not a good thing. You want radiation to be stopped _before_ reaching your body, or for it to go right _through_ your body. Stopping _in_ your body is what you try to avoid.

[@Dimmez]

1. "Cookies are good for you" - Cookie monster (Premise) 2. "Radiation is bad for you" - Some professor (Premise) 3. Therefore, radioactive cookies are neutral (Conclusion) Secondly, if air can stop alpha rays, then surely liquids can aswell. So there is some truth that vodka protects you from radiation (especially if you eat alpha ray cookies). Man those Russians are smart.

[@TheConjurersTower]

@@Dimmez Not the science we deserved, but the science we needed.

[@charlesdahmital8095]

Threw my gamma out the window. She hasn't talked to me since.

[@gyrgrls]

If she hears you say that, she'll beta you up.

[@aka0989]

i guess she doesn't bake you cookies any more :(

[@MrMeszaros]

I bet she hasn't made gamma cookies for You either :D

[@danielculver2209]

Now I know my ABCs Next time she won't be deceased

[@fungdark8270]

Try that with my gamma and alpha q up

[@brianbender7438]

Incredible job! I have watched it twice and at least once more to come. Having a good teacher can make all the difference. Thanks

[@karhukivi]

Might be worth pointing out that while alpha and beta particles are "stopped" by a certain thickness of material, gamma photons and neutrons are not exactly "stopped" by lead and paraffin respectively. Rather they are attenuated by the thickness of the material to a greater or lesser degree. There is a corresponding "half-thickness" (like half-life) which is the thickness that reduces the intensity to 50%. The half-thickness is mainly a function of density (for gamma radiation) and also the energy of the gamma photons. The half-thickness of lead for x-rays might be 3 mm but for high-energy gammas it might be more than 1 cm.

[@michaelschwartz9485]

All these videos are great but the eat, sit or throwing of the cookies really drove the point home! I gotta watch it again.

[@theonionpirate1076]

I'm only a minute in, and I can tell this man is an excellent professor and I'm going to learn from this. P.S. Did I just play Fuck Marry Kill with radioactive cookies?

[@kabloosh699]

And learned that the gamma cookie is the least destructive cookie to eat as well.

[@commie281]

@@kabloosh699 not so fast, that’s assuming the half life and concentration of the radioactive material is the same.

[@kabloosh699]

@@commie281 I think logically speaking you shouldn't eat any cookie giving off large amounts of radiation regardless of what version it is.

[@commie281]

@@kabloosh699 of course haha

[@originalketchup7498]

@@commie281 wow you are almost as dense as Pu

[@elrolo3711]

This is excellent tutorial to understand the basic concepts. He has the best tone and slow pace to allow us to absorb the info.

[@LA_Viking]

I first heard the "cookie" routine in the middle 1970's when training for radiation emergencies. The 70's version used four cookies, 1 each alpha, beta, gamma, and neutron. The options were as follows: throw one away, hold one in your hand, put one in your pocket, and eat one. The largest difference was that the "older" version assumed (correctly) that an alpha would be stopped by surface layers of the skin. It also assumed that betas would be stopped by player of cloth (debatable). It's an interesting teaching tool in any case.

[@ntm4]

I learned that one in the Navy (worked on the support systems for the nuclear power plant, so we cared a lot about neutrons).

[@igorgerlovin3185]

I would DEFINATELY throw away the neutron cookie!!! Neutrons are the worst!!!

[@LA_Viking]

@@igorgerlovin3185 Thank you for your reply. Definitely a wise choice. Since it had no charge it can go through a lot of tissue wreaking havoc along the way.

[@ThePiXbO]

I really got addicted on those videos, they are awesome and well explained! Also I love the way of talking, because I'm deaf and with the voice I can hear it more properly!

[@12gauge1oz]

Excellent presentation, Yes, and the ability to write backwards is impressive. Very informative, thank you.

[@tigertiger1699]

Clearly… a very intelligent guy.. super good teacher…

[@rivertonrentalswy]

What an excellent teacher and brilliant man.

[@willyjimmy8881]

Never seen something so complicated explained so simply.

[@functionalvanconversion4284]

This is the part of college I miss, hearing great lectures from interesting professors. I don't miss the stress of midterms and finals 🤓

[@SeattleSandro]

I don't miss lectures from professors who are great researchers, but terrible teachers.

[@passedhighschoolphysics6010]

Excellent - One of the best explanations of ionizing radiation ever presented.

[@Quantiad]

Sitting on the gamma should've been 1/4, as half goes towards your body and by the logic applied to eating it, half of that stays in your body.

[@YodaWhat]

Most of the gamma rays will pass right through a human body, and where they do react, the damage will not be concentrated in a small region. Charged particles, on the other hand, deposit 90% of their energy in the last 10% of their travel, leaving concentrated damage. That is why particle beam radiation is the best kind of radiation treatment for cancerous tumors, and usually better against a tumor than chemotherapy, which typically attacks the entire body.

[@Quantiad]

@@YodaWhat I'm simply talking about consistency in the basic logic he applied to his chart, nothing more.

[@YodaWhat]

@@Quantiad He oversimplified.

[@Quantiad]

@YodaWhat - He obviously oversimplified. Again, I'm commenting on consistency, not accuracy.

[@naphackDT]

Yes and no. It's more complicated than that. Remember, gamma rays penetrate your body completely, so you catch whatever the absorption rate of your body is, multiplied by the distance traveled by the radiation(simplified). If we keep it in this simplified form, the distance remains the same since the radiation will penetrate your whole body regardless and thus you catch the same radiation. Of course there is the inverse square law, so the further you are from the source of the radiation, the less rays will actually hit you simply by virtue of distance, but with oversimplified maths, the radiation would remain the same.

[@kalemercer7053]

Great video, one of the best explanation of radiation with out the fear mongering the news pushes out.

[@jackroman8821]

Absolutely excellent presentation, very well done. Clearly explained and well diagrammed. Love it!

[@mcintoshdev]

You are the most awesome teacher ever. Your knowledge about nuclear physics is not only fascinating but you present your material perfectly. I envy your students and enjoy this channel.

[@parkershaw8529]

Let me emphasize on the cookie experiment, do NOT forget the premise is all the radioactive sources have the SAME energy level.

[@SkitFireS]

Ya this threw me off too, I'm used to gamma sources being much higher energy.

[@packratswhatif.3990]

Yup, me too, eat the gamma because we are the ugly bags of water to stop the radiation.

[@bobjackson4287]

This got me too, first intuition would say sit on the Alpha, eat the Beta and throw out the Gamma. This of course depends on dosage volume. The problem with eating a decay product is that it will keep "cooking" you from the inside out, And any type of radiation is dangerous when inside your body when in high amounts of ionization. Typically the things emitting gamma are materials you really do not want to be eating at all. A lot of them will kill you from the toxicity of the metal rather than killing you from exposure.

[@BradleyLayton]

The same energy portion threw me off too. Is it the cookies that all have the same energy, or the individual discrete emissions that have the same energy? How about the power? Is the energy in each of the three cookies being released at the same rate? I would also be nice to see a few more significant digits on those nine probabilities.

[@ameunier41]

​@@BradleyLayton I think that he basically meant they are equally dangerous.

[@markmazza135]

Love these because Dr Ruzic is so down to Earth. I wish he was a neighbor so I could ask all the questions about nuclear physics that come to mind.

[@puncheex2]

It seems important to me to note a couple of things about shielding. Air is a shield for everything. If not the best, it is the most common. Alpha particles are stopped by 3 cm of air (2 inches); beta by a meter (3 ft) of air. Gamma rays are real EM - they aren't stopped by air, but they do get absorbed, half of the energy in 200 meters (600 ft) of air, or attenuated by a factor of 32 per km, a factor of 128 per mile. Neutrons are also absorbed in about the same rate, at least for the neutrons created in bombs and fission reactors. In water, all radiations are capped at about a meter in water, even if the source is the worst encountered on Earth: fresh spent fuel rods. So I say, throw them all in the water.

[@uploadJ]

re: " they aren't stopped by air, but they do get absorbed," Actually absorbed, converted to heat, or is this a spatial dispersion, a one over R squared phenom? Since gamma is an EM wave, I'm thinking its more of an one over R squared dispersion phenom ...

[@jacbbnib]

I went to a function and watched you for hours, you saved me

[@TGNXAR]

To all those commenting on how amazing it is that he is writing backwards so quickly and so well; have you considered that he is writing forwards normally, and then mirror imaging the video?

[@BBaaaaa]

Yes, you can see it by the hand his clock is and how he uses his hand out of the dark "illustrations" part, it's def flipped

[@Paid2Win]

Smurt

[@TGNXAR]

@@Paid2Win It is ingenious.

[@jcp5231]

wouldn't that make the particles antimatter?

[@drananth]

This is a wonderful presentation for the fundamentals of Nuclear Medicine. Thank you.

[@srinivasanandhini5393]

I m SRINIVASAN. I clear doubt sir 9865081922. [e-mail] Please contact number sir.

[@k.chriscaldwell4141]

Neutrons are indirect ionizers. When they impart kinetic energy to a proton (+), the proton is sent on an ionizing path through what contains it.

[@jasoncummings7052]

Well structured, presented and informative. Been four years but thank you.

[@nobiledigitale]

A video like this should have 300000000 views, non 400. Then maybe people would stop spewing nonsense.

[@viktormolnar]

You absolutly thrue

[@russellhamner4898]

He needs to start espousing flat-earth theories for at least half of each video to get people to actually watch this stuff.

[@Chironex_Fleckeri]

Most people watch a show like HBO's Chernobyl and think, "yup. I knew radiation was bad." That's the extent to which most people care to investigate. It's called the Dunning-Kruger effect, and it has a lot of damaging consequences for society.

[@ryutenmen]

@@Chironex_Fleckeri I dont deny that Dunning-Kruger effect its real. In fact, that's the problem - possibility of being real, because if Dunning-Kruger effect is real, then Dunning-Kruger effect could be a Dunning-Kruger effect, meaning - If person A(pretty smart one) say about B person(the not so smart one) that he is "suffering" of Dunning-Kruger effect, then after a point, the person A could "get" Dunning-Kruger effect, thinking is to smart for simple people, thus his evaluations are not good because they are actually "infested" by Dunning-Kruger effect ;) This Dunning-Kruger effect is a double-edge sword.

[@nobiledigitale]

Ok it’s still not enough but in 3 weeks it went from 400 to 65000. Not bad

[@larrykent196]

Thank you for the video. A lesson in radiation and logic. Cheers to that!

[@acoow]

A second reason to not eat the alpha cookie: Since alpha is stopped so easily, it will do greater damage to a smaller area. Also, its double charge (two protons) means that it does more damage. It ionizes more atoms before it stops.

[@robinwells8879]

I wouldn't miss one of his lectures for all the tea in China but I might pass on the offer of an afternoon tea with him! 😉

[@pixxelwizzard]

Loved this whole series. So well explained, easy to understand, and expertly presented. Thank you!

[@mingklytus]

I love these videos. Thank you Professor

[@Thestuffonmainstreet]

Fantastic info! Helping everyone understand that scary radiation better

[@kingarthurthe5th]

“Unless you’re wearing thin aluminum pants…” Yes! CaUsE i’M DeFiNeTLy NoT wEaRiNg aLuMiNuM pAnTs!

[@trevorfarren2186]

Excellent presentation, gotta be a great teacher! Great paradigms too.

[@cantsolvesudokus]

But the greatest mystery ever remains: how does he write onto thin air?

[@floddarelti206]

Magic

[@Pa-lg2si]

lol

[@CS80undermybed]

He's obviously got a thin-air pen. They are very popular over here in the United Kingdom of England-Land ;-))

[@xtralarsproductions]

@@CS80undermybed Thats quite the username you got there xd

[@tekman2000]

Thank you VERY much, your explanations are always so clear and thorough 😀

[@oibal60]

Sitting down, listening to Kraftwerk's Radioactivity right now, eating an apple, will throw away the core.

[@MB-rc8ie]

:D

[@ZachHixsonTutorials]

Ok, that match-cut at 2:20 was spot on. Don't know if you did that intentionally, but it was pretty trippy lol

[@Roodj1]

Amazing instructor, seems he really enjoys his subject. Edit: can we give him props for writing backwards with really good handwriting skills.

[@iankeeler7431]

There's a comment like this on a lot of his videos, but almost certainly he is writing normally, and the footage is simply flipped in post, the easy way to do it. Further evidence: He appears to be writing with his left hand. Only about 10% of people are left handed. In the videos of his class demonstrations (ways to block radiation) he appears to be right hand dominant. You can also see his watch and wedding ring (both typically worn left) switch as well. Unless you were being sarcastic? lol

[@gyrgrls]

No, but we can give him jets...

[@Skinny-me]

You are a wonderful teacher! I wish i had you as my Physics/Chemistry teacher in school 50 years ago! :) - Thanks!

[@ThomasAllen90]

Ok eat gamma - it views me as empty space? sit on alpha - pants will stop, so throw out beta - for someone else to deal with

[@dr.spectre9697]

Wish I was your student.....PLEASE keep uploading more videos!

[@dake4629]

Wouldn't sitting on the gamma be more like 1/4? 1/2 goes to the floor, and of the 1/2 that hits you - half (1/4) fails to hit anything. So the final dose would be the remaining 1/4, right?

[@JesterAzazel]

Maybe even 1/8, because the remaining 1/4 going upward would be cut in half because of it going through you as if you were empty space.

[@skidancin]

Yes...which fact made me think less of this guy.

[@ryutenmen]

How the fuck did you guys get from "1/2 that hits you" to "Maybe even 1/8"? If 1/2 hits you, how can you say that half of 1/2(meaning 1/4) fails to hit anything? What happens with "1/2 hits you"? Half(1/2) is the same as a quarter(1/4) for you guys, or even less(1/8)?

[@dake4629]

@@ryutenmen The space between the atoms that make up the matter of your body tissue is quite large. Example: If the nucleus of a single atom was at the pitchers mound on a baseball diamond, then enlarged to the size of an orange, the first ring of electrons to circle it would be in the bleachers. So its easy for one orange to pass another orange in that scale and not collide. So, by the time a gamma particle passes all the way through the trillions of atoms of your body, it only has a 50-50 chance of ever hitting a single atom of your body. So that makes only 1/2 of the gamma passing through you harmful. Meanwhile, only 1/2 of the total gamma particles being emitted, are even passing in your direction, the other 1/2 is going down thru the chair and passing into the floor. Therefore, 1/2 of 1/2 is 1/4. I think the post about 1/8 is incorrect, but the whole concept is overly generalized anyway, just for sake of illustration. Cheers

[@rickj1983]

Excellent explanation, very interesting and easy to understand.

[@craigroth8710]

Fantastic presentation!!!

[@FixItStupid]

If you like the minimization of the health risks to the world.... Propaganda to minimize..... For more money For more money more money more money more money

[@jonathanmeazza427]

I want to go back to school, this guy is amazing.

[@pepe6666]

oh man i was so smug when he first mentioned the cookie test but i was totally all wrong and it makes sense. wooaaeey awesome

[@armadillotoe]

It was very counter-intuitive.

[@adamschaeffer4057]

Still a bit confusing but I think it's answered with the "same level of power" condition. Isn't gamma radiation more dangerous because it does more damage? Difference between being shot with a BB going 200fps which would sting locally but not penetrate, and a BB going 22,000fps which would penetrate through and through. That's why I guessed wrong and assumed it would be "safer" to eat the alpha.

[@Daniele_Zanardini]

A Great professor, very clear on explanation. Maybe the best on the net for atomic/nuclear issues. Great also for the ties, pure 80' style

[@georgesears2916]

An interesting real life example of a "radioactive cookie" would be the Polonium-210 (an alpha radiation source) used to poison Alexander Litvinenko in 2006. Conversely, I assume the radioactive substances used to trace blood flow in the human body are examples of a "gamma radioactive cookie" as these can be detected outside the body.

[@sharii906]

May you live long for sharing vital science.

[@Marinealver]

When talking about "high energy" particles is it the inertia that the particles contains?

[@kantyDarius]

Yep

[@silversurfer1967]

This guy just made the chemistry that i never understood in high school look so simple

[@zapfanzapfan]

Make this guy the secretary of the Department of Energy!

[@JustinKoenigSilica]

... But why? This makes no sense.

[@zapfanzapfan]

Because he knows stuff and isn't a politician and he is good at explaining things so that maybe even politicians can understand (they usually lack education in the natural sciences).

[@russellhamner4898]

DAMNIT, I was sure I had my cookie test aced. I had the alpha emitter correctly guessed as the one to sit on, but I had the beta & gamma emitters flippety-flopped. Next time I'm gonna just bribe a nerd to take my test for me, except I'm invariably the nerdiest guy in any class so that may pose a challenge. Love the vidz!

[@andrewpoison]

shouldn't it be 1/4 for "sit on gamma", since half of it radiates in another direction and the other half is passing through you entirely with a chance of around 50%?

[@TheRealCoyote]

Yes. Or ⅓ or whatever. Doesn't change the order but you are correct.

[@heinzerbrew]

I think he forgot. The values he has allows for two equally correct answers

[@johns1625]

Yes but then you have to eat one of the other two

[@stuart124]

That cookie model is brilliant! I'm definitely stealing that.

[@Martink9191]

it seems that his chanel have been boosted up lately. Videos are old. Most comments are week or two old. And from comments it refflects that a week ago there where only 300 views instead of 3000 now.

[@siggyincr7447]

Yeah, I hadn't seen them in my feed before about a week ago and now all of a sudden they are all over it. I'm guessing that some bigger channel promoted this channel and that started a feedback loop of increased exposure. The more people that watch a video/channel the more it gets recommended to people who watched videos similar to the people who have already watched it. If the content is good and people watch the entire video, a sleeper channel can take off in a short amount of time.

[@zapfanzapfan]

And now it is 60 000. I guess he reached critical mass ;-)

[@helphelpimbeingrepressed9347]

@@siggyincr7447 Or the Prof sacrificed an innocent to the algorithm...maybe

[@chikkai2432]

Great way of entertaining and teaching in the same time ☺️

[@wvufanew1]

I eat gamma cookies every morning and haven't had a cold or been sick since.

[@gyrgrls]

I like the uranium chip cookies, myself. Except when my roommate cesium, he'll seize 'em.

[@kjadfhgioaudbfvilaeu]

Just mix them with some naturally sourced organic breast milk and some essential oils and you have the elixir of life.

[@panspermiahunter7597]

That is so strange you should joke of that, I practice anapanasati follow your breath meditation and I have not had the cold or flu since I started 6yrs ago, just thought I would tell you that.

[@hifiandrew]

These videos are excellent. I wish we'd had these in high school or college.

[@PabloA64]

There should be a "love this" button right?

[@gyrgrls]

Why? Facebook does, so it's only fair YT lacks a love button, since FB lacks a dislike button. :D

[@CrumpetsNBiscuits]

That last test, with eat, sit and throw got me. I admit i was wrong. Good explanation.

[@HappyFlapps]

My Great-Great Gramma Madame Curie made delicious cancer cookies.

[@wisconsinfarmer4742]

Yeah, gamma is pretty great.

[@info_fox]

Thanks for working on the marker noise. It's getting better. Really enjoy your content.

[@adlervomnorden7571]

Note #71 Dear diary, today I learned from a physics professsor that I shouldn't eat Alpha nor Beta radiation. 📒

[@gustavderkits8433]

All cookies are radioactive, to a good approximation. But thanks for the useful problem

[@brunotulliani]

Love this series! I am curious to know which "ray" I can use on my mother-in-law to put her in a good mood? Well after this lecture we can forget about gamma rays because she is always "smash" mode!

[@helphelpimbeingrepressed9347]

Well we threw beta rays out of the window. So I guess you're saying you need alpha Ray to "smash" your mother-in-law...does your wife know you have these thoughts? :P

[@johnpacheco5404]

Wow. Totally thought throwing out the gamma was the way to go.

[@originalketchup7498]

This is why the ignorant shouldn't comment on science and just listen to fucking experts

[@Goreuncle]

@@originalketchup7498 Eating a cookie that emits gamma radiation isn't smart. The particles that don't get through will definitely cause damage. Don't swallow arguments from authority, they're unscientific in nature. Evidence and facts are all that matters, titles and honors mean nothing in comparison. If a scientist can't make a strong case without resorting to arguments from authority, that's a lazy scientist who doesn't master the subject. The great Isaac Newton got proven wrong by a clockmaker (John Harrison), when his clock was used to measure longitude with sufficient accuracy, something that Newton didn't believe was possible. "I have told you oftener than once that [longitude] is not to be found by clock-work alone. Nothing but astronomy is sufficient for this purpose". These aren't the words of a scientist, these are the words of an inflated ego that refuses to even consider the possibility of precision clocks. Why? Idk, maybe Newton couldn't bear the thought that a carpenter turned clockmaker could be a better engineer than he was 🤣. Due to Newton's opposition, Harrison was denied a hefty cash price, as reward for having solved the longitude problem. It was only after Newton's death that Harrison was finally granted the price. Scientists like Newton are cool when they follow the evidence, but when their egos get in the way, it's better to just ignore them. Newton forgot the Royal Society's motto "Nullius in verba" (take nobody's word for it).

[@Goreuncle]

@John Pacheco Throwing out the gamma is definitely better than eating it, but it's even better to remain at a safe distance. If high energy radiation were safe, radiologists wouldn't be required to operate x-ray machines from a separate room and astronauts wouldn't have to worry about their dose.

[@pavel9652]

​@@Goreuncle Dose is what is makes it lethal. Radiologists do scans every day, so this is their occupational hazard.

[@pavel9652]

This is a common misconception, since gamma is the hardest to stop, except the neutron. Alfa is far worse when ingested and this is the risk. Look for the biological impact. I have seen some estimates of how much worse it is, but can't find it now. Some unstable isotopes are similar in the chemical structure to other stable elements and end up built into the tissue, where they dump the whole radiation for a long time. Alfa particles are heavy and they hit molecules hard.

[@fredo3161]

I enjoy these videos. I've always had trouble grasping atomic science and whatnot.

[@dsandoval9396]

5 minutes in and I just realized he's writing backwards (right to left) in front of him, so we can see it left to right.

[@launch4]

Actually look at which hand h's writing with. Unless he's left handed he is writing left to right. I think it's just reversed in post production.

[@donwall9632]

Dumb arse. You are wrong I guess you are 20ish if that

[@prabhatgupta3356]

Very eye opening and full of knowledge

[@84gssteve]

"Very interesting"...….(puts tinfoil hat back on, snugly)

[@gdgtrekker]

So you’re only interested in stopping alpha and beta particles...

[@Gogglesofkrome]

@@gdgtrekker he'd have to put on something more than three layers of space suits made of lead to even begin to stop high energy gamma radiation.

[@henryarrington3446]

Where was this dude when I was in college ? I might have stayed. Lol. Excellent presentation.

[@simon199418]

its alright guys calm down, the backwards writing works in Greek too

[@abhinavralhan2217]

Wonderfully explained...too good

[@Chironex_Fleckeri]

Im trying to set a world record for most CT scans received! Ill see you guys in the record books!

[@ganeshjunghare4198]

You can write backwards. This is awesome.

[@eprofessio]

I drove through Illinois this past week and it is a complete decaying sh-thole.

[@ZIlberbot]

thanks Prof for such vivid examples !

[@Volksgenossen]

Nuclear power is vital to the survival of the human race. The consequences of using fossil fuels far outweigh the consequences of using nuclear fuels. Keep up the great work professor! People fear what they do not understand.

[@amoscordell6544]

I really enjoy your lectures. I was in charge of radiation protection on board a US nuclear ballistic missile submarine in the 1980s. When I left the Navy I went to work at a new nuclear powered electric plant in Georgia doing health physics I had been there less than a year when the accident at three mile island occurred . I thought then that nuclear power was doomed. I think we just have become more knowledgeable and safe about it. If we could just solve the high level waste issue, those spent fuel pools are getting full.

[@ericsmith8373]

Interesting tidbit. Ever wonder where the helium in your kid's party balloons comes from? It comes from alpha particle emission. Radioactive elements in the Earth's crust decay via alpha particle emission. These alpha particles grab two electrons from somewhere and presto, you have a helium atom. Helium is produced as a by-product of oil and gas production. Mostly gas production.

[@goerizal1]

amazingly a very good teacher. thanks.

[@katieell4084]

Why is that amazing?

[@dhardy6654]

I get the physics....but the amazing part is how does he write backwards?

[@ryutenmen]

@phục êwê It seems that you are dyslexic ;)

[@kevinbroderick3779]

The image is flipped horizontally, like a selfie camera.

[@Nikowalker007]

The video is mirrored ))

[@dhardy6654]

@@Nikowalker007 ha! Physics!!!!

[@testy462]

Instructions unclear, gained 25 lbs. And I still don't have any super powers.

[@PointyTailofSatan]

No tachyons? I'm a physics major, I think I have been asked about tachyons at least three times. Too much Star Trek. lol

[@katieell4084]

They're totally real. Probably. Maybe. Probably not.

[@xapemanx]

you are also adding distance when you're adding the lead, which is another factor at reducing exposure

[@BBaaaaa]

Thanks for the info, i did not think it was a factor, didn't go through ny mind lol

[@TheRealCoyote]

Yes, naturally. But not why it got quieter in this case (insignificant). But when working with radiation distance is your friend. Double the distance=¼ the dose.

[@companyoflosers]

the impressive part is he is writing backwards from his perspective.

[@matthewgrotke1442]

Or the entire film could have been flipped in post production.

[@cbell9100]

Camera facing a mirror

[@pappaflammyboi5799]

Pb210 is a β- (beta negative @ 100%) emitter, not an α emitter (alpha emitter with < 1.9 x 10^-6 %). Maybe you meant Po210 (Polonium 210) which is an α emitter, but it's quite dangerous to handle so I hear. Excellent presentation by the way.

[@zapfanzapfan]

Definitely don't eat the Po 210-cookie, or drink the tea...