Hank explains the whole story about radiation - the good, the extremely helpful, and the bad.
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Either the abbreviation "IDTIMWYTIM" is wrong or Hank is saying it wrong. "I Don't Think That Means What You Think It Means" would be "IDTTMWYTIM"... or is it a Meta-Joke, because IDTIMWYTIM doesn't mean what he says it means?...though I guess it still means the same thing...
I'm bookmarking this and sending it to the next poor ignorant soul who claims that microwaves and cellphones are akin to chernobyl and hiroshima. Mainly because I get really tired of explaining it. This topic could easily be expanded to discuss the concept of ionizing radiation dosage and cover why a single dental x-ray is really nothing to worry about.
When I was younger I worked t a store that sold direct TV. A lady asked me if the dish was safe and did it give off radiation. I said "It's safe because it only gives off 12 curies of gamma rays per day. Gamma rays have a wavelength much smaller then dangerous things like Xrays." She said (trying to sound smart realizing it was a dumb question) "Oh well that makes sense if it's the rays are shorter" So yes shorter is less then something so less must mean it's safer; that just common sense. Now if we didn't have consumer protection law and regulations all one line of reassurance and you can sell people something totally dangerous like the fluoroscope in the shoe store
Visible light can be thought of as "semi-ionizing" because even the lowest energy (longest wavelength) visible, red, although it does not IONIZE atoms, it can EXCITE electrons in CERTAIN PARTS of certain molecules, such as chlorophyll (the excited electrons fall back to unexcited levels, transferring energy to other molecules, in a chain reaction that ultimately produces GLUCOSE and OXYGEN (from water and carbon dioxide), for the plant, and eventually animals, to oxidize to make energy), and the pigments in retinal cells (the excited electrons cause chain reactions with other molecules to send signals to the optic nerve.
Visible light also causes other biological reactions, none of which are harmful. Also, while "far ultraviolet" can cause cancer and sunburn, "near" ultraviolet, the shortest and "reddest" UV, causes vitamin D to be produced in the skin.
Melanin is evolved expressly to defend the skin against (UV) radiation damage, although strangely in spite of being very efficient at converting blue to ultraviolet light into heat, it does not correspond to a particularly high sun protection factor, so people with dark skin still need to use almost as much sun protection as people with pale skin. This seems to be the main evolutionary reason we have skin colour, and actually the evolution in the case of paler skinned people has been a loss of colour in order to increase efficiency in producing vitamin D in our skins in climates where we could otherwise become deficient in that vitamin, which is mostly produced in our skin rather than consumed in our food. It's colour or color depending on your country, both us Britons and Americans likewise have derived our word from a Norman French original, which was presumably similar to modern French couleur. Actually, the American version matches the Latin original from which the French word was ultimately derived, but given that the pronunciation does not correspond with either the Latin or the French and does not match the spelling either, I think we can fairly say that we're both making it up. No one spelling is better than another, they have just been chosen by someone along the way who said, "This is the best way to spell this word." The were probably wearing a shiny black hat of some kind. The kinds of people given to saying and writing those sorts of things often wore shiny black hats as far as I can work out.
As an 11 year old just learning this, I find he really breaks down the definition of it and this definitely helped me understand it more. It's also somewhat funny which makes kids enjoy it and probably memorize it better. I'll be sure to tell my teacher to share this with the class so whenever I talk about it people don't start staring at me like I just called their mom a fat ogre. Thanks, mate! :)
Hey, just wanted to point out, you said that alpha is the least ionising and gamma the most. I am pretty sure however, that alpha particles are the most ionising but the least penetrating, while gamma rays are the least ionising and the most penetrating, and beta particles are in-between.
Wi-Fi is 2.4GHz (even 5.8GHz nowadays) while cell phones (at least here in North America) uses bands from around 700Mhz to 2100MHz (2.1GHz). Historically, cell phones used lower frequencies while newer standards tend to use higher frequencies. This is why cell phone are still said to use normal radio wave despite both of them being in the microwave range.
Aren't beta particles less ionizing (by 1/2) than alpha particles, but much better at penetrating things? In high school, we learned that ionizing ability goes down from Alpha to Gamma, but penetration goes up.
Lol at penetration
But yeah, alpha particles are much less penetrating than beta particles for two reasons: firstly, alpha particles are helium nuclei making them really big while beta particles are electrons an neutrinos which are volumeless and incredibly light. Second, beta particles are shot out near the speed of light (somewhere in the upper 90%) while alpha particles are fairly slow.
To answer the ionizing part of your question, you are correct. Helium is the most electronegative atom on the periodic table, and it's an ion of 2+, so it will rip electrons from anything (even fluorine I believe). As for electrons (since neutrinos don't interact with anything really save bumping into crap sometimes), they are at high energy (since they're going to fast) so they can wreck shit, but aren't as bad as an He^2+ ion.
The cellphone cancer thing has always been absurd to me.
Every part of your body is emitting infrared radiation just by being even close to Earth-like temperatures.
Microwaves carry less energy to mess with your DNA than infrared radiation, which carries less than visible light.
Basically, every atom in the universe warmer than the cold depths of space is emitting more energetic radiation than what your cell phone produces.
Microwaves have about as much ability to change your DNA as sound waves do.
I once heard this kid say "a girl got cancer in the same side of her head that she used her cell phone." That's like saying an elephant caused a building to collapse because it was the only elephant within 100 miles.
Radiation goes through lead, just like anything else (that isn't too exotic). Like in biology, it's the dose that makes the (nuclear) poison.
Why most of the gamma rays of a source can't get through a meter of concrete ? The same reason it can't get through a few centimeters of lead, or a denser material. But get something like a sheet a few nanometers thick, and most of the energetic photons (the "rays") will pass through. The denser the material, the higher the probability that a photon will hit matter while it travels through it, and so be stopped before it exits the material. And so, the thinner your shield will need to be to protect from the same amount of radiation.
Therefore, you would need 6cm of concrete to equal a 1cm thick lead shield!
um..... beta particles (electrons and positrons that are beta minus and beta plus) are NOT more ionizing than alpha and LESS than gamma radiation, they are LESS ionizing than ALPHA and MORE than GAMMA radiation.... but they travel bigger distance than alpha and less distance than gamma radiation.... alpha particles are helium cores (that's 2 protons + 2 neutrons for you) stripped from electrons and are BIG (compared to beta electrons and insanely enormous compared to gamma photons) hence the shorter travel distance (the bigger you are the more stuff you hit) and the bigger ionizing power (the bigger you are the more stuff you hit and the harder you hit) it's like comparing a whale a care and a mouse traveling at 100 miles per hour what does more damage?
Alpha has greater charge (+2) than beta (+/- 1) or gamma (0), and that is the reason it is more likely to interact, not size. However, from most to least ionizing alpha-beta-gamma, which is as you said.
another factor is that gamma photons and electrons are smaller compared to alpha particles.
there is a good chance for a gamma photon to speed through your body without interacting with it at all.
there is also the chance for an alpha particle to crash into your dead skin cells where it doesn't do anything significant either.
the real danger of radiation is that you don't usually have one kind without the other two being present somewhere near, when a gamma ray ionizes an atom, that ejected electron becomes a free moving beta particle that can do damage somewhere else.
Hi. Could you do a video about the use of microwave ovens in more detail please? There's a lot of stuff going around on the internet that seems completely over the top negative so some clarity would be a good thing to have. Thanks.
hi there! I found some "computer radiation protection classes" (by accident). I havent known much about computer radiation. Because I study the whole day with my laptop (and my eyes get tired in the evening), I researched a bit (but havent found sth really helpful). Do you think it's worth it to buy these glasses or is this just humbug?
+comb528491 X-ray does not have temperature, nor do micro waves. Actually X-ray tubes are hot. The cathode heats up and ionizes giving off electrons which are moved to the anode at high speeds. As it hits the anode with tungsten, kinetic energy is converted to thermal energy and X-ray.
Also, what makes the food hot in microwaves(machine) are the microwaves that vibrate water(and some food) molecules giving it kinetic energy. According to the Kinetic Theory, a higher kinetic energy would mean higher temperature.
I think you got the relative ionizing power wrong.
Since alpha particles have plus two charge, they have the strongest ionization power. Now ofcourse because of their heavy mass they can be stopped quite easily, but, that's the penetration power right?
indeed. a helium nucleus will take any electron it comes across and once it has two it will never give them back.
gamma radiotion is just as ionizing (two charges per particle) as the ejected electron itself can ionize another atom.
the real difference is that there is a good chance for a gamma particle to speed through your body without hiting anything so you need to get exposed to quite a lot of it to be significant, while alpha particles, if they somehow get past the layer of dead skin cells covering most of your body, will deal some real damage and you won't need much of that to notice something is wrong.
+Banderi first of all let me know a bit more than wiki (masters in nuclear physics and technology) second of all you did not understand what i wrote, neutrons INTERACT only directly electrons and alpha particles INTERACT directly and indirectly (because they have a charge) and photons INTERACT only indirectly (no mass) and IONIZATION is a direct function of the probability of INTERACTION, the type of particle/radiation (photons are not a particle) and the energy of the particle/radiation every type of particle ionizes in both ways but the probability is different depending on the type of particle and yes neutron direct ionization is highly improbable but it's not impossible the dominant effect is fission, fusion and beta or gamma emission but direct ionization is not impossible it's just highly unlikely
+fasdr According to Wikipedia, directly ionizing and indirectly ionizing mean two very specific things: "Neutrons have zero electrical charge and thus often do not directly cause ionization in a single step or interaction with matter. However, fast neutrons will interact with the protons in hydrogen via LET, and this mechanism scatters the nuclei of the materials in the target area, causing direct ionization of the hydrogen atoms. When neutrons strike the hydrogen nuclei, proton radiation (fast protons) results. These protons are themselves ionizing because they are of high energy, are charged, and interact with the electrons in matter."
+Banderi actually they ARE directly ionizing, they ionize stuff by hitting it and removing other particles from the atom or by lodging themselves in an atom's core and forcing an atomic reaction governed by the particle and energy conservation principles the result of witch is either creation of a new element, transforming the neutron into a proton by emitting a beta minus particle and an anti neutrino (particle conservation principle), neutrons have almost no electomagnetic charge so they can't interact indirectly (by forcing energy without a physical interaction), photon radiation (gamma radiation) on the otherhand is the only radiation that's not directly ionizing (and it's not a particle) because it's an electromagnetic wave (a photon that has no mass) that is absorbed by an atomic particle and if the energy of that photon is at a certain level it can either excite that particle and when the particle that absorbed it relaxes it releases another photon with a different wavelenght or it can give enough energy to that particle (almost always an electron) enough energy to free it from the atom (photoelectric effect) they cant interact directly cause they have no mass, only charge....
+BenAddict19 Yeah, everybody already pointed it out the mistake in the comments, you're kinda late. That still doesn't mean the video is false and the general information in it is incorrect. People do still believe anything associated with the word "radiation" is malicious, and in such context this video is more than plenty for them to listen to. I highly doubt anybody incapable of discerning between ionizing and non-ionizing radiation will bother to account in the order between alpha, beta and gamma.
+Jesse Versluys Actually broccoli in vinegar or a spot of pickled cabbage will clean out your insides, and then any room you are in for several hours afterwards. People will again return to the room once all of the evil that was inside you also leaves the room - opening a window helps.
Millions of cells around your veins/vessels would be killed, and hundreds or thousands of them would become cancerous and kill you within a day or so... And you can find an alpha source in most smoke alarms (it acts like a security trip wire that gets blocked when smoke is in the way)... Please don't take a smoke alarm apart because it would attach to the dust around it and you would breathe it in!
Penetration depth and energy to ionize are not caused by the same thing. Absorption is measured with barnes and A B and G are three very different things. Gamma is EM (photons/waves) while beta and alpha are electrons and helium nuclei respectively. EM will react with electrons through the electromagnetic force and so will beta. Beta will also interact though the weak force. Alpha will interact though the strong force and not EM as the charge of the two protons is masked by the speed at which it travels making it relativistic where the particles mass comes from its speed much more then its mass. Really it's too much to put in a comment let alone an entire video to understand how the forces work and why penetration and ionization are not directly proportional.
I'm guessing you got some training to work with nuclear reactors, but not nuclear engineering or physics. This is an educated guess based on your comments. You learned some intro level stuff, and now you think you know all that there is to know. I'm not saying that the crap you're spouting is entirely wrong, I'm saying it's not entirely right...it's also incomplete.
+Jozzarozzer i also will submit this
X-ray and gamma radiation are best absorbed by atoms with heavy nuclei; the heavier the nucleus, the better the absorption. In some special applications, depleted uranium or thorium are used, but lead is much more common; several centimeters are often required. Barium sulfate
is used in some applications too. However, when cost is important,
almost any material can be used, but it must be far thicker. Most
nuclear reactors use thick concrete shields to create a bioshield with a
thin water cooled layer of lead on the inside to protect the porous
concrete from the coolant inside. The concrete is also made with heavy
aggregates, such as Baryte
or MagnaDense (Magnetite), to aid in the shielding properties of the
concrete. Gamma rays are better absorbed by materials with high atomic
numbers and high density, although neither effect is important compared
to the total mass per area in the path of the gamma ray.
please answer this 1 question how heavy is the nuclei in paper?
+Jozzarozzer no i do get that. the question is how much paper would it take? yes it is basic high school science. but its also basic math! how thick would the layers of paper have to be? simply put to have enogh paper to stop gamma radiation the paper would have to be so thick that you would be almost as far away as to out distance the gamma radiation anyway! do the math!
See this is what you don't get, the material doesn't matter. No matter the density of the material, you can just increase the amount of it. Paper can stop gamma radiation, you just need more than what can stop beta which needs more than what can stop alpha. This is basic high school science.
+Banderi Continuous Positive Airway Pressure.... It's my breathing machine that can be monitored -remotely- due to the WiFi connection...thus = non-ionizing radiation....which I can 'turn off' if I keep it in 'Airplane Mode:. Clear as mud now?? LOL. I just hate the idea if any radiation emitting right next to my bed, by my head. OMG. and I refused to have the new digital meter readers installed on my home for the same reason...... yet here one is ....IN my BEDROOM.
I feel as if he could have explained ionizing radiation better. Beta particles, alpha particles, and gamma rays. All of these can be thought of as both waves and particles. While trace amounts of ionizing radiation come from external sources, the magnetic field of our Earth protects us from much of it. Radioactive elements present the most dangerous threat of ionizing radiation. These elements are unstable and break down over time, releasing ionizing radiation. Alpha particles consist of 2 protons and 2 neutrons(identical to helium nuclei). When an alpha particle is released, the elements atomic number decreases by 2. In this way the element may decay into a different element. The mass of an alpha particle is about 3.7 GeV. They are stopped by a piece of paper or human skin. Beta particles are electrons or positrons(positive charged electron). They may travel outwards at incredible speeds, surpassing 75% the speed of light. The mass of a beta particle is about 0.5 MeV. This makes an alpha particle approximately 7400 times as massive as a beta particle. Gamma rays are just photons with extremely high frequency and energy. They have no mass.
I can't believe how badly they got this wrong, alpha is the most ionizing and gamma is the least, but gamma penetrates much much more than alpha (ie nothing can fully stop gamma and alpha is stopped by air)
What do you mean very low frequency electromagnetic waves aren't super useful? Mains electricity is a very low frequency electromagnetic wave, and that's doing pretty well in powering my computer. Come to that, I think it might also hurt me too if I'm not careful.
I can safely inform you that radiation has almost nothing to do with nuclear energy, and bears little of the known danger characteristics. Radioactivity is in fact, the activity of radios, the presence of radio waves in the air. Ripples in the fabric of the universe around you. As you may know, radio waves are considered long wavelengths of light, so long that you cannot see it. This is untrue, and the sight of them are simply blocked by a surgical incision at birth. The effect of these surgeries can be negated however, most effectively with LSD and marijuana, hence the government's reasoning for illegalizing the drug. Green wavelengths are the easiest to see, and this is because it is by far the most dangerous, but also the most effective at controlling an innocent citizen.
I think you have your ionizing radiations backward. Alpha is the most ionizing (net charge ++), but tends to be easily protected against, beta is significantly less ionizing (net charge -) but requires a little bit more effort to protect against it--you don't want a strong beta source on your skin for very long at all) Gamma rays are ionizing because they occasionally excite electrons to a high enough degree that they will leave orbit around the atom's nucleus (net charge - when it actually happens), The rate this happens at depends on the energy and frequency that the gamma is carrying, as well as the bond-strength of the electron with it's atomic core, but basically for terrestrial sources will always be lower than the rate at which alpha and beta ionize a localized area. There is no effective way of completely protecting against gamma radiation, and that is why it's nasty. Dense substances like lead or gold will absorb a lot of gamma, and it will disburse to lower rates with increased distance from the source, but you will never successfully absorb or avoid all of it. If there is a source of gamma radiation, some level of exposure is inevitable. This level is normally low, and our metabolisms are designed to deal with it's effects. The problem comes when you start to rapidly get a large dose and it overcomes the body's protective mechanisms, or over the course of a lifetime as those mechanisms wear down along with the rest of the body.
Hank! Did you say the title of this show wrong? It's supposed to be IDTIMWYTIM but you read the title as IDTTMWYTIM. Caught a "THAT" where it should have been an "IT". All your shows kick ass so I'll let slide. Haha.
Hank! Did you say the title of this show wrong? It's supposed to be IDTIMWYTIM but you read the title as IDTTMWYTIM. Caught a "THAT" where it should have been an "IT". All your shows kick ass so I'll let slide. Haha.
In this video, it was mentioned how beta particles are more ionising than alpha, and beta are also less ionising than gamma. My physics teacher and my text book said otherwise... Not sure which one is accurate. Does anyone know?? Thanks.
Yea. What I think he meant was penetrating effect. Your textbooks and teachers are right.
From least ionizing to most ionizing: Gamma>Beta>Alpha
From least penetrating to most penetrating: Alpha>Beta>Gamma
The reason why alpha particle have low penetration is because it easily ionizes and decays before it can even penetrate a paper.
2:24, wait, beta particles are more ionising than Alpha particles, and less than gamma? That's the wrong way round isn't it? That would imply Gamma is the most ionising, and alpha the least?
Gamma is the least ionising, then beta, then comes Alpha by a massive amount, since it is way more ionising.
Gamma however is the most penetrating, then beta, then alpha (stopped by a few cm of air, or a bit of plastic/paper).
+Will B Yeah,the helium is a bad analogy. There. What I mean is, there's nothing stopping an individual gamma photon being much more high energy and destructive than an individual alpha particle, penetration notwithstanding. All we are talking about is tenancies. Of course, the weighting factors used to make the sievert readings tries to factor that out, although I don't know whether they apply at extreme energies. But under that same weighting, gamma and beta radiation have the same weight.
Of course its relative, that's the whole point XD, we are trying to figure out/remember/convince each other under which conditions each is the most lethal and how dangerous they are relative to each other.
Understanding stuff like the following has been the point: A ridiculous amount of alpha radiation can be safely contained in a small jar and safely approached. A smaller amount of gamma-emitters is much more difficult to shield and you generally have to stay farther away to be safe. But if those alpha emmiters get into your body the greater ease of interaction of alpha particles means they are more dangerous than gamma emitters *in that setting*. Of course, sufficiently small quantities of any type can be safely ignored, and likewise too much of any kind will kill you almost instantly. Its the relations and subtleties we were interested in.
Btw alpha particles are high-speed helium nuclei, not atoms, they are given a different name and treated separately from the gas because they act so differently. They are moving too quickly to react chemically with anything and are completely electronless, changing their properties drastically. Its like comparing a bullet in flight with a lead paperweight, though they could be the same size/shape/etc. the actions they perform and the properties you are interested in are completely different. You only start worrying about the it as Helium when it slows down from interacting/colliding with atoms. THEN it may have some weird chemical effects, like yanking electrons off neighboring atoms and and ionizing them. These effects are (I think) mostly ignored when talking about radiation because they are (again, I think) orders of magnitude less damaging than the results of the collisions while the particle is still behaving like an alpha.
Isn't it all relative anyway? If I was around large amounts of gamma rays almost energetic enough to likely pair produce on the cosmic microwave background, I'd be worried. If I was around some very low energy alpha particles aka helium gas, not so much.
+Yamareto You may not be proficient in anything but you did hit that nail pretty much on the head :P. I already knew about the difference in penetrative power but you summarized the relationship between that and its likelihood to cause trouble quite well.
Could you maybe do an episode about radio waves? Maybe I'm just being really dense, but I've been trying to understand how they even work and failing. How can they both translate into sound (AM/FM radio) and into light (like in radio astronomy)? Also, I think I understand how a radio picks up a radio station, because you tune the radio to a certain station (like 89.9 AM), and that makes your radio pick up a station that's broadcasting their frequency at 89.9 megahertz. Cool...but how is this frequency translating the words of the radio host or whatever into the sound I hear on my radio? Because the 89.9 station's waves are travelling at a constant wave of 89.9 megahertz (right?) so your radio can properly pick up the radio station, but how does the wave account for different sound waves, like volume and pitch? And that's not even getting into how TV broadcasting (with images) is supposed to work, and radio astronomy picking up images of the big bang...I am just at a loss.
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