Well thank you for your kind words. Alas I can't always make a video every week due to other commitments. But I am currently working on a video on standing waves (by request) and I will try to get that up next week.
@lapertica82587 жыл бұрын
GREAT. If I had seen your videos earlier I should not have been confused as I was. Thank you and congratulations
@ReviewSquadron11 жыл бұрын
Massive thanks for this. I may just get this degree after all thanks to you!
@kamerl110 жыл бұрын
he described it better than any text I've read, THANK YOU
@paulg4445 жыл бұрын
He is simply the gift that keeps giving !
@mvuyisimbabane5837 жыл бұрын
omg you have no idea of how much this video helped me. i read a couple of books but could not understand, now i get it
@nuhanoor7633 жыл бұрын
This video was really really helpful. I was reading NMR but couldn't grasp the concept of nuclear spin. You explained it amazingly. Thank you!!
@stokhosursus Жыл бұрын
I apologize for my previous comment. It came out much harsher than I’d intended. What I really should have said is that I would love to see DrPhysicsA tackle some of these old topics again since it’s been some time and a lot has changed in video production since this video first came out. It’s a great video!
@bondjish10 жыл бұрын
Great video. We appreciate the effort you put into it.
@Higgsinophysics4 жыл бұрын
What a brilliant explanation - thank you
@herrzyklon11 жыл бұрын
Bob, I'd just like to say that you are a legend.
@awaisamjadmughal72564 жыл бұрын
thank you so much sir, i like the way you made this clear. (A cold breath after watching this video)
@nishugoyal23655 жыл бұрын
hello..!! it was literally a nice and very informative lecture, i am a master student in france ,working in nuclear physics domain, i was looking for some nice explanation about shape coexistence in exotic nuclei. could you please make a video on that too..
@zecarlosparahyba74982 жыл бұрын
Great job, Dr. Physics.
@evebannon72234 жыл бұрын
Found this so helpful! thank you so much
@venkataramireddyappireddyg81047 жыл бұрын
Thanks a lot. I used your videos to teach my students
@jimdogma989012 жыл бұрын
Another awe-inspiring video Doc, thanks. I look forward to these weekly videos more than the weekly Breaking Bad episodes! Couple questions. 1) what happened to the saxon-woods-saxon model? I got geared up for that and it was gone? Also, you mentioned something about either the protons OR the neutrons acheiving the magic number. Does that mean there's a seperate shell arrangement for each, or can we combine nucleons to achieve these magic numbers. Thanks Doc.
@golsson945 жыл бұрын
Thank you for the clear exlpanation, it helped me alot!
@ahmedashraf-14585 жыл бұрын
Thank you very much. Very well explained.
@DrPhysicsA12 жыл бұрын
I suppose the key thing is that whatever theory is developed has to accord with experimental observations. The standard model is generally regarded as the best fit with what we actually observe.
@MarkRLeach10 жыл бұрын
Hi, love your stuff! Somewhat pedantically, there is a minor error at 6:32 and again at 6:37. You add two elements to the ionisation energy chart, but these should have been added _before_ the noble gas element(s), not after. There are no elements on the 'down slope' (as I know you know). Keep up the good work. Mark Leach (Dr.)
@DrPhysicsA12 жыл бұрын
I didn't dwell on the WS potential in what was intended to be an overview of the shell model. The magic numbers apply to protons and neutrons separately. So if for example both the number of protons and neutrons in a nucleus are magic numbers (eg Calcium 40) it means both proton and neutron shells are full.
@Samuntiedekanava7 жыл бұрын
Very inspiring and clear explanation! Thanks!
@red-baitingswine88165 жыл бұрын
Great explanation - a lot of exactly what I was looking for. How can the protons and neutrons form separate "shells"? Don't the strong forces act between all nucleons equally?
@red-baitingswine88162 жыл бұрын
@@TriNguyen-he7xk Thank you.
@DrPhysicsA11 жыл бұрын
The shape of electron orbitals is really just a consequence of the wave function (which depends on the electromagnetic potential between the electron and nucleus - and other electrons) and indicates the probability of finding an electron at any given point. There will be a similar effect for protons and neutrons within the nucleus altho of course they are subject to a much stronger nuclear force which makes them more constrained. There will still be a prob of finding them cos subject to Pauli.
@climbeverest5 жыл бұрын
This is an incredible lecture
@abigailmolusi648310 жыл бұрын
it makes things much clearer
@valmormn6 жыл бұрын
What a great explanation!
@nosirovabdurahmon59642 жыл бұрын
Please continue with isospin model and cluster model.
@michaelt92667 жыл бұрын
Thank you so much, you did a better job than my university lecturer in a shorter amount of time
@Dowstairs0711 жыл бұрын
Very good explaination in this video, helps a lot to understand basic physics! 1 Thing: in a sqare well potential, shouldn't there be E~n² instead of n?
@qewqeqeqwew397710 жыл бұрын
Energy levels in a square well are not equally spaced.
@Waranger57 жыл бұрын
correct, that would be the harmonic potential. I think you need Woods-Saxon because neither harmonic nor infinite well gives you the observed magic numbers, even when accounting for spin-orbit
@quarksarranged5 жыл бұрын
@@Waranger5 Woods saxon would only work if you account for spin orbit.
@kingmerkulov17546 жыл бұрын
good video i finally managed to understand the enery levels thing
@akashashen12 жыл бұрын
Excellent 100th video. Congratulations and thanks for creating and sharing. Sincerely, Like #7
@samking470710 жыл бұрын
Really helpful video, hopefully this will get me to pass my exam in 2 days!
@michaelbenn506210 жыл бұрын
i hope you failed
@nourajchhetri73876 жыл бұрын
I love physics. Thank you sir..
@debiprasad00811 жыл бұрын
very good explanation, was really instructive and fun to learn the physics
@JK-yj8oy9 жыл бұрын
Thank you so much. It is really helpful and found it very useful.
@EliottDucarme5 жыл бұрын
Good explanation plus cool accent make for a really good vid !
@vinayanand60566 жыл бұрын
Thank you sir for sharing your knowledge.
@seonaxus9 жыл бұрын
For the quantum numbers at ~ 20:00 should it not be ms is +/- 1/2 as s is always the same for a given particle.
@steliosgeorgiou92348 жыл бұрын
DRPHYSICS YOU ARE A GOD
@jaguaroar8 жыл бұрын
+Stelios Georgiou you're a loser
@steliosgeorgiou92348 жыл бұрын
you are a dweeb and probably filthy bieber fan
@jaguaroar8 жыл бұрын
is it too late now to say sorry?
@rohitjha897811 жыл бұрын
Now that is an understandable introduction! Finally a great video on you-tube! So when is the next video lesson on Shell model coming out?? Thank you for the lesson!
@enmanuelpadilla18017 жыл бұрын
Thanks a lot, for this explanation..!
@vicpinas787710 жыл бұрын
Hi Sir great video, still I need to ask something I was calculating the energies for some nuclei but using the Dunlap equation chapter 5, I face a great deal of problems and my answers does not match the answers given by Dunlap . Pleasecan you help here Thank you Vic
@BretVarcados9 жыл бұрын
~ Please tell me if I'm wrong, but: I would theorize that the attraction between the protons and neurons, and the strong force is regulated by the electrons cumulative amplitude of energy, which are held in orbit to the nucleus due to the laws of completing electric currents, and their need to ground before changing polarity. Protons being the point of force against electrons, and the neutrons are a force of attraction, which is defined as the Culon force. Thus the interactions between protons and nucleons are minimal other than giving polarity and mass to an energetic particle, because the laws of magnetism would be forcing the protons and neutrons to settle in relatively equally spaced and alternating positions, which form a circular shape and space thanks to the cymantics of sound, substance, time and space. ~ What do ya think??
@jordanfox8407 жыл бұрын
Such a formulation would fail to explain basically all of nuclear physics. For example, nuclei can be dissociated from their electron cloud in a plasma, yet the nuclei do not dissolve themselves. Nuclei have energy levels, as seen in this video. Nuclei can transition those energy levels, in part, through radioactive decay. Interactions between protons and neutrons are not minimal - they give rise to a breadth of phenomena that do not depend *at all* on the electron cloud being there.
@muhammadtalhaanwar66495 жыл бұрын
Great lecture.
@leazeslad5 жыл бұрын
great video, thank you!!!
@loistownsend371010 жыл бұрын
Thank you, great video! If you had to add in parity into these for the excited state configurations how would you go around doing that?
@jimdogma989012 жыл бұрын
Doc, where's the next video in the series? We look to you for our weekly harbinger of hope to sail us through this turbulent Dirac pool of life.
@nikoskoutsilieris16247 жыл бұрын
you are fucking amazing!
@dacilrodriguez46939 жыл бұрын
Soooo helpful!! Thank youu!!!!
@rajkumardutta54525 жыл бұрын
In atomic structure we do not have 1p level or 1 d level etc. But in nuclear structure we have 1p, 1 d, 1g etc. Why? Can we really refer 1 here as principal quantum number?
@samb18_kite7 жыл бұрын
@DrPhysicsA Sorry, but how can square potential wells have equally spaced energy level? it varies as square of n. LHO has equally spaced energy levels.
@FelipeZucchetti12 жыл бұрын
Sorry, it may look a stupid question, but do have the ammount of nucleons a role on the electrons stability around the atom?? I mean, in order to be stable, do the atoms need a particular ammount of electrons around them?? By the way, thanks for your videos...i watch your channel since your begginings and i've learn a lot with you...
@RR-yx5ux10 жыл бұрын
I was told that the number in front of the letter is only the shell for the atomic notation, and that for the nuclear shell it's just a way of ordering the levels.
@tomaskadavy10 жыл бұрын
Thank you very much.
@kayodeajulo83776 жыл бұрын
i like this tutor
@antoinegar.63810 жыл бұрын
Many thanks!
@jimdogma989011 жыл бұрын
Are the quantum numbers and orbital energies for the nucleus products of the shrodinger equation (SE) as they are for the electron orbitals? If so, the SE solutions for the electron orbitals specify a shape for those orbitals. Does the maths that determine the nuclear energy states specify shapes for their orbitals-shells?
@ronistiawan11307 жыл бұрын
Thank you so much !
@earldcosta97852 жыл бұрын
Thanks
@DrPhysicsA12 жыл бұрын
Thanks for kind comment. I'm not aware that atomic stability is determined by number of electrons. It's much more determined by nature of nucleus (eg atom becomes unstable if more than 92 protons). Complete electron shells produce inert gases.
@rishichandrawawhal32749 жыл бұрын
Amazing!
@elinope47453 ай бұрын
protons, much like everything else, cannot be monopolar. They do not have a positive magnetic charge, they have a magnetic charge that is on average positive. But there is a north and south to it's charge, it is not universally positive. For exactly the same reasons not all electrons are negatively charged, although they may be on average negatively charged. The negative and positive of the charge only comes up for the field and not the individual hadrons/leptons.
@t4k3none11 жыл бұрын
Thankyou. Seems a very esoteric subject, but it is exaclty what I was looking for.
@marina49195 жыл бұрын
Do we know magic numbers because we know where the gaps are, or do we know where the gaps are because we know magic numbers?
@azharulislam42935 жыл бұрын
what is the success and limitation of magic number?
@DrPhysicsA12 жыл бұрын
I fear so. You have to make the maths work. And its jolly hard.
@samwelimathias1192 Жыл бұрын
Thanks much Dr l got light
@enchis12695 жыл бұрын
is there any rule for the arrangement on binding energy levels? i got curious because the 2s(½) is appeared when the value of n is 3
@MisterTutor201011 жыл бұрын
In the graph @6:36 would the low points be occupied by the group 1 alkali metals?
@kousoulides12 жыл бұрын
But what is the standard model nowadays, the string theory says elementary particles are one dimensional objects other say they are 0 dimensional.. The reason I am asking is because I was wondering lately if a black hole emits positively charged particles, and shrinks down. why can't it be shrinked to a theoretical stable point that it only holds a few particles into orbit. (atom) why does it have to evaporate. I guess I better start doing equations and see for my self why.. right?
@syuhada96276 жыл бұрын
thankyou so much!
@ritzch76323 жыл бұрын
Thnks sir
@TheImpressionable9 жыл бұрын
What happens to the notation once you get past l=26?
@sarikasingla11446 жыл бұрын
Thankuuu...so sir...really u r amazing....
@kousoulides12 жыл бұрын
it seems to me that all these forces inside an atom exist on the assumption that elementary particles do not have substructures. If all that there is is those particles then you need to have forces. But why can't an atom be a collapsed spot and the elementary particles interpreted like.. hawking radiation into orbit of that spot ..I mean they do behave like they pop in and out of existence, they do entanglement similar to the radiation.. why not?
@sajateacher8 жыл бұрын
Does the Heisenberg Uncertainty Principle play into this somehow in terms of the size and interactions of the nucleus?
@jordanfox8407 жыл бұрын
The HUP should not be involved with the form of the nuclear interaction. Uncertainty principles are not physical things, but rather it is a result of the mathematics used in the model. Depending on your physical system, you might have a different looking uncertainty principle. Quantum is done in infinite dimensional Hilbert space where "measurements" are made by applying self-adjoint operators to wavefunctions. It turns out the uncertainty principle for that space is the HUP. That also doesn't mean the HUP is not a *real* thing - it is - but it manifests in the experimental process and not in fundamental physics.
@mongoika389810 жыл бұрын
Excuse me, isn't the principal quantum number in the lowest energy n=0 in the case of nuclei, and if so, why isn't the orbital called 0s?
@DrPhysicsA10 жыл бұрын
No. The first principal quantum number is 1.
@DrPhysicsA10 жыл бұрын
***** Yes you are right. And that is what I was trying to convey (tho I agree it isn't as clear as it could be). I'll add an annotation to clarify. Thanks for spotting it.
@muhammadsohailkhan89476 жыл бұрын
Sir how a nucleus have a spin of 3/2, 5/2, 7/2 etc
@bedahfisika3 жыл бұрын
That's not spin, that's a new quantum number which describe how much proton can occupy in the state
@donwald3436Ай бұрын
14:48 my brain suddenly blurted out "van de Waals?" and now I'm wondering if the valence quarks inside the nucleons could deform their position probabilities for something to happen there. Just another physics crackpot lol.
@MsSris20116 жыл бұрын
Thank u so much
@federico-bayarea11 жыл бұрын
Great video! I have a question about the Pauli exclusion in electrons and the concept of spin. When we say that two electrons cannot have the same quantum numbers, and for instance in the first shell one must be spin up and the other spin down. What spin axis x, y or z are we talking about? Is it on any axis we choose or a fixed axis that depends on the atom? Basically, why could not an electron be in x axis and another on the y axis? Not possible, but I would like to understand it. Many thanks!
@jordanfox8407 жыл бұрын
This is a good question, but the answer might not be very satisfying. When you say electron spin could *be* on a x-axis or y-axis or z-axis, the quantum founding fathers start twitching in their graves. The process of measuring the components simultaneously is impeded by the uncertainty principle. For a single-particle wavefunction, a single component of spin can be known simultaneously with the *magnitude* of spin, but no two components can be known simultaneously. In practice, experiments measure components either in a transverse (z) or perpendicular (xy plane) directions, but it depends what you are doing. In the end, the restriction that a wavefunction has a good quantum number is a restriction on the result of a measurement, and due to uncertainty that measurement cannot give us the whole story.
@brendawilliams80622 жыл бұрын
Thankyou
@okotray45775 жыл бұрын
Like this
@kousoulides12 жыл бұрын
I am not a physicist by the way I am a computer programmer .. here download my game on the iphone: puzzle flights! :P its free (it's for kids though but hey)