this is the most clear explanation of the way alpha particle or indeed any thing coming out of the nucleus, classically and "quantumly"referenced with simple math in between. This way I discover is excellent and allows one to answer his own questions, which are necessary for understanding any non-simple system like radioactivity. I hereby congratulate DrPhysicsA for their excellent exposition.
sir your videos are so nice and easy to understand .....I'm a physics honours student .....my final year exam will held on next year march ....please make some videos on atomic physics and special theory of relativity ......thank you sir ...
Very Nice Video, thanks. The only question i have is where the alpha particle gets the energy to tunnel in the first place. Is it because when the alpha particle forms in the nucleus some of the mass of the protons and neutrons is converted into energy (so the mass defect)? Thx for your help anyways. Going to see some of your other videos too. :D
I'm thoroughly confused on one specific matter. At 7:34 and 9:39, you use the same written symbol for two different functions, under different names. The first, you seem to pronounce 'e' (like the first e in electron), and the second, it seems like you refer to it as "log." Would you mind clarifying this, please?
It little confusing regarding coulomb potential at the edge of nucleus. A free alpha particle inside nucleus having positive charge should have no difficulty ejecting out of positively charged nucleus so shouldn't coulomb potential energy should be negative rather than positive at the edge of nucleus. Then there will be no need for quantum tunneling.
Yes, this was confusing. It makes sense for an alpha particle brought in from infinity -which is how I've seen it described other places. It also works to explain it in terms of having energy consistent with experiments. It does not mechanistically explain the "barrier" to an alpha coming out of the nucleus. I would like to know what prevents the alpha from leaving the nucleus closer and picking up more energy from the coulomb force - I assume it is actually the short tail of the nucleus potential.
Right! Trying to understand the ‘danger’ of alpha and beta radiation .. I think I wrongly presumed that the energy released during alpha decay was gamma rays .. Now I think I understand that the alpha particle has kenetic energy, travelling at high speed that can damage our cells (in laymen’s terms) is that correct? ... Would that be the same with the electron in beta decay? .. I get the gamma ray radiation dangers
I'm trying to reason as to why the coulomb force creates a potential that the alpha particle cannot overcome. I know this is me thinking pretty classically, but is it because the alpha particle is still, "inside" sort of a wall of other protons? Like they're just nudging it backward and it just quite doesn't have the Q to overcome it easily. So it needs to tunnel in order to get on the other side of the rest of the protons? I know you said it's much more fuzzy than that, but I just want some sort of intuitive idea of the situation. Thanks!
Heh, thanks. At least I can pretend now that it all makes sense, haha. BTW thanks for all your vids. So many are a nice break from reading the text. I get to just kick back and see how much of the reading has stuck.
I think he just did Nuclear Physics as his main in College and then after his PhD in Nuclear physics he went on to study all the other branches of Physics by himself as in he self-taught himself.Probably he was just passion over Physics.
Just a question, Why does nature prefer lower energy states? What i mean by that is why does nature prefer everything to be stable? Doesn't that go against entropy? That everything always gains entropy? Entropy is way out of my current education range so forgive me if there is something about entropy i am missing.
i think entropy is related to macroscopic configurations which might prefer to be "stable" but in reality are not (it depends on temperature). it is a measure of disorder and therefore related to stability but not perse
Arigisel Ahasuerus Aebli-von Glarus-Windegg van Oranje-Nassau, Lord of Frisia to Batavia So what you're saying is that entropy and stability are perceptions? I can agree with that. It reminds me of Scrodinger, it implies consciousness inteferes with physics, yet wave-particle duality and his weird cat experiment have been proven using mathematics and experiment. (not sure about the cat one though, but im sure there is some ridiculously complicated maths involved).
in so far as time is also a perception. perhaps. but very fundamental "perceptions".. entropy comes from statistical mechanics/thermodynamics and is also related to computer/information theory. Consciousness interferes with physics, maybe, yet in a sense also creates physics, but many disagree with that
Arigisel Ahasuerus Aebli-von Glarus-Windegg van Oranje-Nassau, Lord of Frisia to Batavia If entropy is part of statistics, then why is it called the measure of order? Order is merely a perception, so measuring a perception is still subjective to what people percieve.
Nice explanation. I think it would be great if you can make your videos shorter and leave the calculations in a blog or in some documents in cloud drives. Thank you.