Bohr Definition and 198 Threads

  1. H

    What Is the Bohr-van Leuven Theorem and Its Significance in Quantum Mechanics?

    Bohr - van Leuven Theorem ?? Has anybody heard of this theorem? I remember vaugely that it has to do something with the work being done on magnetic dipoles / spins. I can't find it anywhere on the internet. I'm really curious... Thanks!
  2. F

    Calc K-Shell X-Ray Series Wavelengths for Zirconium Atom

    Calculate the three longest wavelengths and the series limit for the K-shell x-ray series of the zirconium atom. (a) λ(Kα) = 79.8832 pm (b) λ(Kβ) = 67.401142 pm (c) λ(Kγ) = 63.90653 pm (d) The series limit is _____ pm So I have solved parts a-c. For part d, the series limit, I tried...
  3. M

    Understand the Bohr Model of H-Atom's 1s2p Splitting

    [SOLVED] Bohr Model of H-atom Hi, Would anyone be good enough to explain why the 1s2p splitting in a hydrogen atom is 3/4 of the total binding energy? Would it have anything to do with the Rydberg energy? E = - 13.6eV/n^2 I appear to have floated through my degree blissfully...
  4. W

    Bohr Radius - what happens when n=100?

    Homework Statement i have been given a question that asks to me to calculate the radii of the first, second and third 'permitted' electron orbits in hydrogen. I did this fine by using the Bohr Equation, each time just changing the n value to either 2 or 3 resulting in the first value of the...
  5. M

    What is the formula for energies of a Bohr atom in a weak magnetic field?

    I have this problem to solve, but I can't seem to find the right formula. It says to use "an expression for energies of a Bohr atom in a weak magnetic field". I've looked in my coursebook but I can't find anything useful. Can anyone help me?
  6. T

    Bohr Quantization Rule for Angular Momentum

    Use the Bohr quantization rules to calculate the energy levels for a harmonic oscillator, for which the energy is p²/2m + mw²r²/2; that is, the force is mw²r, where w is the classical angular freq of the oscillator. Restrict yourself to circular orbits. So far I have that mvr=nh\, w=v/r, and...
  7. M

    Is the Bohr model of the atom still valid in quantum mechanics?

    Why does in QM the electron does not fall toward the nucleus? After all, the only force between nucleus and electron is attractive (- electron and + nucleus). Is the same reason that justifies the moon does not fall to the earth?
  8. E

    How do I calculate the radius of bound states for muonic hydrogen?

    Homework Statement Hi I'm having difficulty in understanding how to calculate the radius for certain situations. for example, I have a question that asks me to calculate the radius and binding energy of muonic hydrogen. Homework Equations The Attempt at a Solution my first...
  9. 8

    How Does the Uncertainty Principle Invalidate the Bohr Model?

    Why the uncertainly relation ΔxΔp>h forces us to reject the semiclassical Bohr model for the hydrogen atom?
  10. hagopbul

    How Do Spin and Stability Interact in the Bohr Model of the Atom?

    Atom But? I am studying atom and I reach the Bohr model & the quantum theory of atom for now. But I have some point that I don’t understand for example: 1st We assume that the positive charge (protons) and 99% of the mass (neutrons) are stable, (in most cases), in the center of the atom .And...
  11. B

    Calculate the physical properties of a Bohr atom

    Homework Statement What is the radius of the n=1 orbit in C^5+ ? What is the energy of the electron in that orbit? What is the wavelength of the radiation emitted by C^5+ in the lyman alpha transition Homework Equations 1/lambda=R*(1/(n^2)-1/(m^2) )...
  12. B

    Calculating Hydrogen Bohr Orbit Transition and Series using Wavelength 410.7 nm

    Homework Statement Light of wavelength 410.7 nm is observed in emission from a hydrogen source. a) what transition between hydrogen bohr orbits is responsible for this radiation? b) to what series does this transition belong to? Homework Equations1/lambda=Z^2 *R(1/n^2-m^2) , n being the...
  13. I

    Find the electric field produced by the atom at the Bohr radius

    an electron is distributed around a proton according to the volume charge density \rho = A e^{-2r/a_o} where A is a constant, a_o is the Bohr radius and r is the distance from the center of the atom. Find A: we know that Q=\int \rho dV = -e i was wonder if this was the integral that i set up...
  14. B

    Effective Bohr magneton?

    The bohr magneton is e hbar/ 2 m If we're talking about an electron in a metal or semiconductor, should the effective mass be used for m? From all the papers I've seen, nobody does that. They just use the free electron mass. For instance the Larmor precession of an electron moment. The...
  15. M

    Why Can't the Niels Bohr Model Be Applied to Other Elements?

    Hi, we know that we can find the radius and energy of the orbits of hydrogen.now why is it so that we cannot apply the same formulas for other elements by using the equations given by bohr.if there are complications what are they?
  16. M

    Which Bohr orbit does the electron occupy in this atom?

    Homework Statement he potential energy of a hydrogen atom in a particular Bohr orbit is -2.72 10-19 J. (a) Which Bohr orbit does the electron occupy in this atom? (b) Suppose the electron moves away from the nucleus to the next higher Bohr orbit. Does the potential energy of the atom...
  17. N

    Bohr Magneton experimental value

    Dear PF, Could you please advise me where I can find the up to date experimental value of Bohr magneton with its uncertainty? Thanks a lot
  18. X

    Bohr radius for single electron orbits

    for ions with more than one proton ie. He+, Li2+ and Be3+, doesn't the extra charge factor into the equation? because it seems only the elementary charge is http://en.wikipedia.org/wiki/Bohr_radius" , hence rendering it independent of amount of positive charge present.
  19. I

    Bohr Model missing momentum question

    In the Bohr atomic model, electrons move between shells having angular momentum L_n = n h_bar where n is the shell number and the difference in shell energies E_n2-E_n1 matches the Rydberg energy of the emitted or absorbed photon. My question is: what hapened to the angular momentum...
  20. Demystifier

    Would Bohr be born if Bohm were born before Born?

    In http://arxiv.org/abs/physics/0702069 I discuss a hypothetical historical context in which a Bohm-like deterministic interpretation of the Schrodinger equation could have been proposed before the Born probabilistic interpretation and argue that in such a context the Copenhagen (Bohr)...
  21. H

    Bohr Energy Levels: Explaining the Concept & Equations

    Im doing a paper on Bohr Energy levels and I need help. The most I can find about the Bohr models are about its radius, velocities, and such. Is there any links that can explain to me clearly the whole concept of the energy levels and all equations attributed with it, if any.
  22. P

    A few questions about the Bohr model

    I was just doing some last minute review for my physics final tomorrow, and I have a few question about the Bohr model of the Hydrogen atom. 1) So at the ground state, a bound electron has -13.6eV energy. Now, say there was a photon with 14eV fired at it... would the electron escape? I mean...
  23. F

    The Bohr Model of the Hydrogen Atom

    The electron in a hydrogen atom is in the first excited state, when the electron acquires an additional 2.86 eV of energy. What is the quantum number n of the state into which the electron moves? I found the answer to be 5 but I don't know how. I thought I could use the following equation...
  24. S

    Bohr energy equation and Ionization energy

    Hey, I was wondering if anyone could help me out with this. I need to take the Bohr energy equation ( En= -2.178 x 10^-18) (Z^2 /n^2) and the Inoization energy equation ( IE= Einfinity - Eground state). I need to somehow modify the bohr energy equation that can be used to find the inonization...
  25. T

    Bohr Model: Calculating Wavelengths of Emitted Photons

    Hi, I'm having trouble on the following question: A singly ionized helium atom is in the ground state. It absorbs energy and makes a transition to the n = 3 excited state. The ion returns to the ground state by emitting two photons. What are the wavelengths of the lowest energy photon and...
  26. N

    How Does the Bohr Model Explain Ionization Energy in Hydrogen Atoms?

    Q: From the Bohr model of the Hydrogen atom, calculate the minimum amount of energy (in eV) an electron in the lowest orbital would need to free it from its proton (i.e., to ionize the atom). A: would I use the equation: En = - 13.6 / (n^2) ? If so, an an electron in its ground state would...
  27. S

    UC Berkeley or Niels Bohr Institute

    I have the chance to choose between on of the above two universities for a exchange semester next year, i was wondering if anyone can give any comparisons between the two in terms of mathematics and theoretical physics. Keep in mind I'm only a sophomore student now.
  28. Y

    Does Bohr Model Contradict Classical Physics?

    a question asks if the Bohr model contredicts in any way classical physics. i replied that only the first assumption that the electrons are fixed in circular orbits violates the laws of classical mechanics - of the idea of centripetal acceleration (?) am i right to say that? did i miss...
  29. R

    Albert Einstein & Niels Bohr Posters

    are there any posters of both Albert einstein and neils bohr? being two of the greatest minds of the 20th century, and the dichotomy between them... i think the poster would say a lot. plus, einstein is my favorite physicist. so, if you know of any, id like to buy one. thanks!
  30. F

    Calculating Energy of Electron in Bohr Hydrogen Atom

    5. The energy En of an electron at the nth orbit in the hydrogen atom is given as: En = - (13.6 / n2 ) eV where n = 1,2,3, . . . . . a, If an electron is at n=3, how many spectral transition lines are possible if it falls to the ground ? For part a, what does it mean by "how many...
  31. A

    Finding Bohr Orbit's Quantum # for 0.01mm Hydrogen Atom

    hydrogen atoms in states of high quantum number have been created in the labortatory and observed in space. Find the quantum number of the Bohr orbit in a hydrogen atom whose radius is 0.01mm. my problem: n=(0.00001/(5.29*10^-11))^(1/2)=434.7 i think that n should be 434, because the...
  32. V

    Quantised Energy Levels - Bohr model

    Hi Guys, Because of the absorbtion and emmision spectrum we know that atoms have quantised engergy levels. For example for an electron to jump from ground state to the first excited state in a Mecury atom, a photon with the exact energy of 4.9eV is required. Now my question is what would...
  33. A

    Memorizing the Bohr Radius: Is it Necessary?

    is the bohr radius an important thing to memorize?
  34. J

    Solving the Bohr Model of Atom: Transition from n=7 to n=5

    Hi; Could someone please help me with this question: By what fraction does the mass of an H atom decrease when it makes an n=7 to n=5 transition? How would I go about this question? Thank you.
  35. W

    How does QM solve the bohr atom problem?

    I have only taken QM for a semester so I'm sure there are a lot of gaps in my understanding. Here is my question: The original electron orbiting around the nucleus like planets around the sun model was rejected partly because the radiation (energy loss) was not taken into consideration. I...
  36. T

    Niels Bohr atom and magnetic fiels

    Niels Bohr atom and magnetic fields Could anyone help me solve the following problem? I am supposed to use Biot-Savart Law. What I tried was: The orbit of the electron can be interpreted as a current flowing in a circular spire (on the opposite direction of the electron's velocity). If an...
  37. M

    The Bohr model of the H atom for anyone who needs it

    hey everyone! good morning! i just took like 15 minutes drawing this to ask a question, but the funny thing is that my question got answered as i was about to post this! :biggrin: :biggrin: so I'm leaving this up for anyone who wanted to look at it! Take care and enjoy! :cool: Note...
  38. J

    How Many Revolutions Does an Electron Make in Hydrogen's First Excited State?

    According to the Bohr theory, how many revolutions will an electron make in the first excited state of hydrogen if the lifetime in that state is 10^-8? Basically do I find the speed of the that the electron moves in this excited state then get the distance that a revolution is and divide it...
  39. G

    Is the Bohr Model of the atom truly feasible given electron acceleration?

    I am currently taking Physics 30 now and we have just finished the Magnetism unit. The last little bit that we had to learn in the unit was about Albert Einstein's Theory of Relativity. I was just thinking about this...and maybe I'm crazy, but I'll just state my opinion. I was just thinking...
  40. M

    Explaining Acceleration of Electron in Bohr Model

    I keep reading that the Bohr model explained why the electron in orbit around the nucleus does not emit radiation even though it is accelerating. How does the Bohr model explain this?
  41. PeteGt

    Does Bohr's Model of Hydrogen Still Hold Up Against Quantum Mechanics?

    I searched the forums to find my answer and didn't find anything within the first couple searches. Here's my question: Bohr developed his model of the hydrogen atom. Then Quantum mechnics came along. Does Bohr's model of Hydrogen work for itself? I always thought even though wave...
  42. A

    Derivation of the Bohr Magneton

    This is a homework problem, and I already turned in the wrong answer (on purpose because I didn't agree with the explanation of why the correct answer was twice mine). I want to know why the answer is what it is. The stated book value is 9.274009 x 10^-24 J/T. I got exactly half that, and I...
  43. Q

    Dynamics of uniform circular motion and bohr model

    In the Bohr model of the hydrogen atom, an electron (mass m = 9.1 x 10^-31 kg) orbits a proton at a distance of 5.3 x 10^-11 m. The proton pulls on the electron with an electric force of 9.2 x 10^-8 N. How many revolutions per second does the electron make? can someone help me solve this...
  44. T

    Suggestions on any good Niels Bohr sites

    suggestions on any good Niels Bohr sites... Taking a summer physical science class..and my presentation is on Niels Bohr...I wanted to know if there were any good sites anyone can point me to. THX :)
  45. M

    Solve the Mystery: Who Said "A Computer Cannot Make a Perfect Model of Itself"?

    Hello, i have a question that the answer is most desired right now..I am in a debate and am looking for a qoute, I think it was either Bohr, Herbert, maybe von nueman, I am not sure, but the qoute is something to the effect that a computer cannot make a perfect functioning model of itself, for...
  46. marcus

    The Bohr compactification of the Reals

    the Bohr compactification of the real line RBohr is essential (it seems) to Loop Quantum Cosmology. Here are some links illustrating that: https://www.physicsforums.com/showthread.php?s=&postid=147432#post147432 I want to understand the Bohr compactification better. It is putting a...
  47. E

    Calculating the Collapse of a Bohr Atom: Larmor's Formula for Power Radiation

    I have a question. Suppose we have an electron orbiting around a proton in a Bohr atom. It is accelerating due to centripetal motion yet traveling at v<<c so Newtownian physics applies. Since it is accelerating, it is radiating energy. Assuming we are using larmor's formula for power radiated...
  48. frankR

    Quantized angular momentum of diatomic gas molecule: Bohr Model

    Here is the problem: A diatomic gas molecule consists of two atoms of mass m separated by a fixed distance d rotating about an axis as shown. Assuming that its angular momentum is quantized just as in the Bohr atom, determine a) the quantized angular speed, b) the quantized rotational energy...
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