Stable Definition and 294 Threads

Is it possible to replace one of the electrons in a heavy atom like uranium with an Antiproton and form a stable atom?

Homework Statement A particle of mass moving in one dimension has potential energy ##U(x)=U_0[2(x/a)^2-(x/a)^4]##, where #U_0# and ##a## are positive constants. (i)What is the angular frequency ##w## of oscillations about the point of stable equilibrium? (ii)What is the minimum speed the...

Hi guys, I am currently writing my dissertation on Graphene and I am investigateing how graphene remains stable, contradicting existing well established theory which states 2D materials cannot exist independently. With the main area of investigation looking at possible lattice distortions...

I'm halfway through the Selfish Gene, and was intrigued by his talk of strategies. Are there any good books that talk about this development in human behavior?

Homework Statement Homework Equations BIBO stability requires, for every input, that the system output y(n) is: |y(n)| ≤ By < ∞ Linear time invariant systems are BIBO stable when: Summation from -∞ to ∞ |h(n)| ≤ Bn < ∞ The Attempt at a Solution For part a, I got the...

Hi all, Typically, we know that the surface tension for water is about 72mN/m at RT. so do this mean that the surface tension over the whole droplet is exactly the same? Moreover, we know that the Laplace pressure may be different over the whole droplet as the curvature in different parts...

When do they emit α, β+ or β- particle to become more stable? From what I've seen in the textbook, β- is emitted when there is an excess neutrons and β+ is emitted when there is a short of neutrons. Then when does an α-particle emitted?

Because torque is force times distance, wouldn't it only take a relatively small force to make a rocket unstable if the force was applied near the base or the top? How is it kept stable? I just saw SpaceX's future plans to make a fully recyclable launch vehicle; I think it is far fetched TBH.

At the last scattering surface (LSS), the energy density of neutrinos is argued to be ~0.68 of the energy density of blackbody photons, based on a thermodynamic equilibrium argument. This is also required to obtain the correct total energy density for stable expansion. At that time, the average...

By "physical particle" I mean color-singlet particles which have asymptotic T=\pm \infty states. How many stable particles exist in the theory? Only one? SU(2), SU(3), and SU(N) gauge groups can all be discussed.

Homework Statement Assume that the atmosphere is dry, and that its temperature profile may be approximated by a linear function in height using a constant lapse rate: T = T_0 - \gammaZwhere T_0 is the ground temperature. Also assume that the pressure can be approximated the following...

I am very confused - any electrons added to dioxygen must inhabit an anti-bonding molecular orbital which leads to destabilisation of the molecule. So why is dioxygen such a powerful oxidising agent? I need to understand this to try and figure out why nitrogen monoxide is readily oxidised by...

Laplace transform includes exp(-st) and s=σ+jω. σ is negative in the left side and hence exp(-st) goes to infinity. It is not stable. Where am I wrong?

Homework Statement Given the following system: s[n] = (\frac{1}{4})^{n}u[n+10]u[n] Prove if this is a stable or unstable system. Homework Equations The Attempt at a Solution I know that in order for a system to be stable, the input must be bounded in order for the output...

Can some one give me ideas that how can we do above question.

Hello again. In the first fork in the road thread I outlined some problems that I am dealing with, and you kind folks offered many suggestions. The 3 big ones that I can remember without looking are: 1) Find roommate. 2) Join Military 3) Work multiple jobs and save up more money. I...

What all the parameters to be calculated to find a vertical standing beam subjected to axial loading stands without buckling or stands stable? My HW problem has a theoretical question, a vertical beam is fixed on both ends. Loaded on the top with axial load. Show that with an example...

Is stable nuclei decay? if no then how and why know please ans me i am waiting

Which one is more stable? I heard that Aerospace Engineers get hired for a job, then get fired. I'm going to be a junior in High School next year and I'm thinking about what I want to be. Thanks!

Hello! I don't know if this is in the right place or not. So if it's not, I won't misplace it in the future. Anyway, I was recently thinking about the orbits of planets around Binary Stars, and was wondering if it's possible to have a similar orbit around the Earth and the Moon. Have a...

Ok, so all elements undergo radioactive decay. But why? I have been snooping around and what i find is that radioactive decay occurs because of instability of the atom nucleus in quantity, proton-neutron ratio and energy content; therefore we have alpha, beta and gamma decay consecutively...

If a small black hole were to fall into a star or brown dwarf, presumably it would initiate accretion and fusion in a shell around it. Can such an object be stable over any decent timescale, or would it undergo variability/significant mass loss/supernova?

?How to know if equilibrium points are stable or not. Is my solution correct Homework Statement Homework Equations The Attempt at a Solution solution above

I know odd-odd nuclei are generally unstable against beta decay as the pairing term in the semi-empirical mass formula is less than zero, and I know even-even nuclei are generally stable, but I don't get the rules you apply for even-odd or odd-even nuclei. Do you have to work out the binding...

Would it seem reasonable that so-called ‘hot jupiters’ are in resonance i.e. have a stable orbit? If one utilized our stellar system as a simulation, with the addition of a hot jupiter, then what would the resonance be? Would it be calculated as non integral? Then if our cold gas giant were...

A one-dimensional force F(x)=(3.0N/sqrt(m))*sqrt(x)-(1.0N/m)x acts on an object of mass m = 2.57kg. a Find the position x0 where the mass is at a stable equilibrium. b Find the frequency of small oscillations around that equilibrium position. How does this compare to the frequency if we...

I have a object of mass m=5.34Kg. There is a force acting on the object F(x)=(5.0N/m[1][/2])*(x[1][/2])-(1.0N/m)*(x). 1)I need to find the position x0 where the mass is in a condition of stable equilibrium. 2)What is the frequency of oscillation around this position? How would this frequency...

The boiling point for R-ethyl 3-hyrdoxybutanoate is about 75 C The boiling point for S-ethyl 3-hyrdoxybutanoate is about 180 C How!? How is the same molecule that much more stable just by rearrangement of the hydroxy group. I'm trying to explain how some R enantiomer may boil off along with...

I am preparing for my control theory exam, but I have come across that I am struggling. I have a third order system and its asking to me determine when a value of an adjustable parameter, K for when the system is critically stable. I just don't know what this corresponds two for a third order...

I understand that Iron3+ has a half filled 3-d level, but I also know that in reality when one electron is lost from elemental iron, the lone pair from the 3-d level will move to the 4s level to stablelize it. What I really want to know is which ion is more abundant in nature? Thanks guys

Hi, What would it take to produce a stable black hole in a particle laboratory? Must one use some kind of focuser and shielder to prevent the initial point from evaporating? In some entanglement experiements, they use laser to remove the thermal agitations in the particles. Can we do the same...

If it didn't escape to space so easily, then would it easily react with other things on Earth's surface?

I was thinking that since the density of something is as much dependent on the molecular structure as the atomic, that there should be some leeway here.

Given the semi-empirical mass formula for the binding energy of a nucleus is B(Z,A)=a1A-a2A2/3-a3Z2/A1/3-a4(Z-N)2/A+delta(Z,A) calculate the energy released in the reaction 28Si +4He --> 32S + gamma. Hence find how long silicon burning will sustain a massive star which has 1Mo of silicon in...

Especially over geologically significant intervals of time? Is cave collapse inevitable?

Does anyone known this, or is this something that is not known. Where is the photon located before it is released? Is it located in the electron?

Hello. I have a function which doesn't work near A=0. I want to change it to something that a computer can evaluate for any value of A. y = [exp(Ax) - 1] / [exp(A)-1] As you can see below, it approaches y=x when A->0. I was wondering about multiplying the numerator and denominator by...

(1) Is there any equation to determine how many neutrons there should be to keep an atom stable? I don't mean mass - number of protons. I mean the equation that can determine an interval of neutrons based on atomic number only and the forces. (2)Why can't there be an hydrogen atom with 6...

I'm going to college next year and I am having a really hard time choosing what to do. I really love physics. It is my passion and I am really good at it. I want to major in physics, but I know getting a lucrative job in that area is not going to be easy. I have been poor my whole life and I...

Hi, I need help with the following numerical analysis questions. The textbook I'm using (Intro to Numerical Analysis by Stoer) doesn't have many examples so I'm having a lot of trouble figuring out what exactly I should be doing. "Evaluating the summation as i goes from 1 to n of a sub i in...

Whenever I think of an ion I think of an atom that can generate electricity. Something powerful. I wonder, if an ionic state is a pretty rare state to be in that only happens under special, and mostly temporary conditions? Or, is my view of ions wrong?

I need help ranking the following from most stable to least stable: -(CH3)2C=CHCH2 with dot over the CH2 -(CH3)2CHCHCH3 with dot over the 2nd CH -(CH3)2CCH2CH3 with dot over the C -(CH3)2CHCH2CH2 with dot over the CH2 the dots represent the primary, secondary, and tertiary radicals...

Could someone please help? The question reads: For which real numbers "k" is the zero state a stable equilibrium of the dynamic system (vector(x))(t+1)=A(vector(x))(t)? A= [0.1 k ## 0.3 0.3] --> a 2 x 2 matrix with ## separating the two rows. So, my thought is I need to find the...

Homework Statement The system with impulse response h(t) = a_{1}\delta(t-t_{1}) + a_{2}\delta(t-t_{2}). Is this system stable or not?Homework Equations The Attempt at a Solution I drew the h(t) response and I got something like that: but I don't really know how to prove it. There is no input...

So mesons consist of two quark. I am wondering why no stable mesons exist?

What's makes an atom stable or unstable? From what I know, if an atom has a mass number Z that is more than 83, it is unstable and would undergo radioactive decay to make itself stable. So, is there any criteria that classify an atom unstable?

Aspiring hard-scifi writer here. I try to make sure details in my fiction are consistent with known science or reasonable extrapolations thereof, unless absolutely demanded by the plot (and even then I try to offer some justification). I'm wondering if the solar system I'm setting a short story...

Homework Statement This isn't really a homework question, but it is part of a lecture powerpoint that the teacher will go through with on Monday and I was just getting ahead so I can understand better. [PLAIN]http://img59.imageshack.us/img59/3088/cuelectronconfig.png Homework Equations...

What is marginal stable airplane?

I enjoy Physics like many and always keep an eye out for new discoveries, but is our understanding of the universe becoming too complicated and involved. We are constantly finding new information that does not fit the current model, but by adding a new constant or variable into the equations it...