Nucleus Definition and 423 Threads

Homework Statement An electron is confined to a nucleus of radius 4 femtometres. Estimate its minimum energy. Homework Equations ΔxΔp_x=h/4\pi E^2=p^2c^2 + m^2c^4 As the electron's rest energy will be much less than it's kinetic energy, E=pc The Attempt at a Solution So I...

Hi guys, essentially I have been talking with my Physics teacher about Beta Decay and she was saying that sometimes electrons come from the nucleus because of the quarks in the protons and the neutrons? I didn't fully understand it so I have likely got it wrong what she was trying to explain. Do...

1.Uranium-235,after taking a neutron turns into Xe and Sr and 2 neutrons or it turns into Ba and Kr and 3 neutrons or many other things. How it is decided that Ur nucleus will change into what? 2.Why aren't we still using fusion to produce energy? 3. Isomers-what's the reason behind the...

Can we give an analogy for nucleus to sun and electrons to planets...... Hi all, Can we give an analogy for nucleus to sun and electrons to planets...... like this in several galaxies... and galaxies together form some other material in larger scale. Also can we say wave nature of...

I am abilogist who recently have to describe medical imaging...In this while explaining Bremsstahlung radiation, I am faced with a question. When a charged partcile like electron approaches another charged particle like nuclues in this case, does it undergo acceleartion or deceleration? since...

Consider the simplest of all possible atoms: A hydrogen atom with only a proton as its nucleus. According to QFT, the electron is constantly exchanging photons with the proton. So, are the electron and proton entangled? Thanks in advance.

I read the following on a page about atomic orbitals (p and d orbitals in particular) which seem 2 me like 3d lemniscates (figures 8 or ∞ rotated about an axis of symmetry to form tear drop pairs or toruses. http://www.chemguide.co.uk/atoms/properties/atomorbs.html Taking chemistry further...

I was wondering why is the nucleus willing to confine itself in one place while the electrons are free to appear anywhere around the nucleus within the orbital. Electrons have this wave function, is there one for the nucleus?

What prevents the electrons from hitting the nucleus? Shouldn't the proton attract it and destroy the atom?

If the free neutron decays in only 15 minutes, why are neutrons in the nucleus attached to protons stable? This has always bewildered me. Just a side question, are 'tetraneutrons' stable or even possible?

The number of protons in the nucleus of an electrically neutral atom is equal to: a) the number of electrons in the nucleus. b) the number of neutrons surrounding the nucleus. c)the number of electrons surrounding the nucleus. d)the number of neutrons in the nucleus. e)None of the...

This is from Paul Davies the Last Three Minutes I thought sound is due to particles moving up and down which activate hairs inside our ear which our immaterial, nonphysical, unconscious mind converts into meaning and communicates that meaning to the conscious mind. I don't see how the...

I have heard that iron is quite special in that no matter how much temp. and pressure is present, it will not change to a molecule of greater atomic number. I keep wondering about the geometry of the arrangement of protons and neutrons in the iron atoms' nucleus that could account for this...

This is just a simple conceptual question. When we try to calculate a nuclear binding energy of some nucleus, we get the mass defect(del M) and find the binding energy by using (del M)c^2 right? Well, what I do not understand is this. For instance, let's take a formation of a...

http://en.wikipedia.org/wiki/Radioac...ng_decay_rates "...which are subject to electron capture in 7Be because (like all s atomic orbitals in all atoms) they naturally penetrate into the nucleus." How can the s orbitals penetrate the nucleus without being captured? And do they mean all...

Homework Statement An electron is held fixed at a distance of 1 m from the nucleus of a uranium atom (Z = 92). If the electron is then released, what is the magnitude of its initial acceleration? Homework Equations I am not sure which kinematic equation that I should use...

and successfully fission. let's say a neutron approaches the spherical nucleus from a particular distance. its possible route to the nucleus has a conical shape. how far from the center can it strike and still fission? If it just nicks it just inside a tangent line will it fission?

A proton collides with a nucleus of nitrogen-14 (atomic number 7). This collision produces a nucleus of carbon-11 (atomic number 6) and what else? My attempt: 14/7N + proton -----> 11/6C + alpha particle? I know it cannot be gamma decay, but I'm not sure if it's alpha or beta decay and what...

1. How much energy is released during the fission of one uranium-235 nucleus? 2. e=mc2 lol :smile: 3. I thought of putting them together but then how to separate them? 1.67495×10-27+3.903 05×10–25×c2=1.7539207313048996244767495×10-7 By the way, the answer is 4.73×10-11

I was doing some reasearch on electrons, and I found that they have both particle and wave like characteristics. Is this the reason why? because they travel in waves around a nucleus? or am I missing a piece of the puzzel? :smile: Cheers

Can someone please help with this one? I'm not sure what to do here. I broke momentum for particles one and two into components (found m1v1cosθ1 + m2v2cosθ2 and m1v1sinθ1 + m2v2sinθ2) but this is not correct and I really don't know what to do. Please help! A certain nucleus at rest...

In the classical view of the electron, would the electron "fall" into the nucleus? I'm not asking why the electron doesn't fall into the nucleus. I know this is explained by quantum mechanics. But in class the other day, my professor said that treating the electron as a classical particle...

This ought to be simple, I think. But I haven't found a consistent way to think about things yet. Is it as simple as adding up all the spins of the elementary particles in the particle and checking whether the total has inter or half-integer spin? Homework Statement State whether the...

Hi,I have an assignment for school where I am supposed to draw a diagram of the brain and label some areas. However, I am having trouble locating the external lateral parabrachial nucleus (PBel) as well as the Dorsal lateral parabrachial (PBdl) (which I assume are in the same general area). Is...

Homework Statement Explain what is meant by Bremsstrahlung. Which cross-section is higher for atoms with Z>1: Bremsstrahlung on the atomic nucleus or on the atomic electrons? Why? The Attempt at a Solution I explained what Bremsstrahlung was just by copying from the notes. I am not...

What if: There are only discrete protons in the atomic nucleus combined with electrons (not the orbital ones) being shared,in some random manner, leaving a net positive charge. The two particles only become discrete with the known different characteristics when the atom is "smashed" and a...

Hi, When a nucleus does \beta-decay _Z^A X \rightarrow _{Z+1}^A Y + e^- + \overline{\nu} The daughter nucleus has one more charge than the mother nucleus, so it will take an electron into its cloud. Why is this electron's contribution to the Q-value said to cancel that from the emitted...

[b]1. Suppose that the potential seen by a neutron in a nucleus can be represented by a square well of width 10^(-12)cm with very high walls. What is minimum KE of the neutron in this potential ? [b]2. K.E = (1/2)mv^2 [b]3. Its an isolated system, so it drops into its lowest energy state and the...

What causes the attraction between electrons and protons in the nucleus? I've always assumed the attraction and worked from there, but I was curious if anybody knows what the root cause of this attraction is.

We were asked to estimate the minimum kinetic energy of an electron trapped within a nucleus having diameter d . My solution was this: find the momentum of the electron (via de Broglie relation) and use a very standard kinetic energy formula, like this (assuming minimum energy state has a...

Hi experts please explain energy levels of nucleus in emitting radiation in MRI

hi please explain what is nucleus shell model?

Wt is meant by the recoil of the nucleus?

So, I know from having taken some QM that solving the Schrodinger equation for an electron with a central potential gives you the probability distribution for the electron, and the different energy levels correspond to different atomic orbitals. That's fine from a mathematical perspective...

The nucleus of an atom has discrete energy states. And most of the time it emits gamma rays and x-rays from the nucleus. If I pack enough atoms into a solid or some other configuration could I get the nucleus to emit visible light. Is there any way I could manipulate the states to get them to...

Homework Statement In \alpha decay a nucleus X at rest decays to a daughter nucleus Y and an \alpha particle. Conservation of momentum and kinetic energy gives: M_{\alpha}v_{\alpha}+M_{Y}v_{Y}=0 \frac{1}{2}M_{\alpha}v_{\alpha}^{2}+\frac{1}{2}M_{Y}v_{Y}^{2}=Q Where the Q value is the...

the nucleus has protons arranged in a small volume then why doesn't the nucleus become unstable due to repulsion?

Homework Statement A ^{238}_{92} U nucleus can catch a neutron with small kinetical energy. Then we'll get a ^{239}_{92} U nucleus. This nucleus has too many neutrons compared to the number of protons to be stable. How can the nucleus achieve a better balance between neutrons and protons...

Can an electron (from outside the atom) collide with the nucleus of an atom, and does this happen at normal energy levels? What usually happens when it does? If it doesn't happen is it because the electrons of the atom repel the incoming electron with their charge. Finally same question, but...

Greetings, I was wondering if a fully ionized atom would interact with a photon. Id expect so but can't seem to find any info about it. Thanks! Physics Novice

I am just a tiny bit confused at what would happen if you shot an electron directly at an ion's (with no electrons like deutrium 2+...) nucleus? would it stop and if so why?

Can an antiproton(negatron) "orbit" around a regular nucleus? Since it's negatively charged like an electron, can it orbit around a "normal" nucleus? Or a more general question: can something be part matter and part anti-matter? Edit: I guess this answers my question...

Homework Statement If the radius of the gold nucleus is 6.47 fm, and the radius of the α particle is 2.36 fm, then what is the minimum required kinetic energy for the α particle if we want the two nuclear surfaces to touch in a head-on collision? Homework Equations Ue=(kq1q2)/r The...

Homework Statement I have a multichoice past exam that does not come with answers. Please help with the following: The binding energy of the X nucleus is 38.4MeV. Which of the following statements is FALSE? a) The binding energy of 38.4MeV represents the mass deficit between the...

Are quarks that made up a proton or neutron naturally entangled at all times? If not. When do they lose entanglement or reestablish entanglement? If they are always entangled. How about between two protons/neutrons or more. Are they all entangled?

I'm sure everyone here will be familiar with the usual graphic or image used to show what an atomic nucleus might look like. Here are two typical images used today; --------- Everybody has seen those images. But in reality, we have no picture of an atomic nucleus, we can only draw the...

I was reading over some nuclear physics and I came across the binding energy of a nucleus. The equation is Eb=[ZM(H)+Nmn-M(AZX)]x931.494 MeV/u I remember seeing this and using this in class when I took it over a year ago but I can't remember exactly how to use it and I see no examples in the...

Homework Statement A neutron in an atomic nucleus is bound to other neutrons and protons in the nucleus by the strong nuclear force when it comes within about 1 fm of another particle . What is the approximate kinetic energy in MeV of a neutron that is localised to within such a region? Take...

What keeps the electron from falling into the nucleus?

Why can you fire neutrons or alpha particles at the nucleus and see interesting nuclear effects but you can't fire electrons at the nucleus? Or can you? I would guess not, otherwise electrons would collapse into the nucleus in every day life. I've heard that doesn't happen because it would...