Calculate Larmor Freq. for Electron in n=2 of Hydrogen Atom

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In summary, the conversation discusses the calculation of Larmor frequency and the allowed values of magnetic energy for an electron in state n=2 of a hydrogen atom in the presence of an external magnetic field. The individual seeking help is unsure of the relevant equations and turns to online resources for assistance. Through research, they come to understand that the Larmor frequency can be calculated using the equation \Delta E = \mu _B mB and the quantum number m=1, and it is related to the energy difference between two states.
  • #1
fluidistic
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Homework Statement


Calculate Larmor frequency and the allowed values of the magnetic energy for an electron in a state n=2 of an hydrogen atom. Consider that there's an external magnetic field of intensity B=1T.


Homework Equations


No idea. I don't have any info on this in my classnotes. So I checked out http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/larmor.html#c1 but I get lost.


The Attempt at a Solution


From my understanding, in the state n=2 the electron can have either a "spin up" or "spin down" (though I never learned yet what is the spin). What I understand from my reading is that if there's an external magnetic field, the electron will suffer a torque and "precess" with the Larmor frequency. But I don't know how to relate this with the state n=2 in the hydrogen atom.
According to hyperphysics: [itex]\omega _{\text {Larmor}}=\frac{eB}{2m_e}[/itex].
 
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  • #3
Spinnor said:
I appreciate your help but there's nothing that can help me there I think. I know that the magnetic field will causes more emission/absorption lines due to Zeenman effect but there's nothing said for "Larmor frequency" in wikipedia and the pictures of the links.
In hyperphysics I found the equation [itex]\Delta E = m_l \mu _B B[/itex]. Not sure this can help me. I also found [itex]\Delta E =g_L m_j \mu _B B[/itex].
I'm actually totally lost.
 
  • #4
I think I got it.
Electron in state n=2 means that the quantum number m can only be -1,0 or 1.
Now I use the fact that [itex]\Delta E = \mu _B mB[/itex]. So I take m=1 for example so I get the value of [itex]\Delta E[/itex]. Then I also know that [itex]\Delta E = h \nu[/itex]. I just have to solve for [itex]\nu[/itex], this is Larmor frequency.
If I said something wrong please let me know.
 
  • #5

To calculate the Larmor frequency for an electron in the n=2 state of a hydrogen atom, we need to first determine the electron's magnetic moment in this state. The magnetic moment of an electron is given by \mu =\frac{e\hbar}{2m_e} where e is the charge of an electron, \hbar is the reduced Planck's constant, and m_e is the mass of an electron.

In the n=2 state of a hydrogen atom, the electron's spin can have two possible values: +\frac{1}{2} and -\frac{1}{2}. This means that the magnetic moment of the electron in this state can have two possible values: +\frac{e\hbar}{4m_e} and -\frac{e\hbar}{4m_e}.

Next, we can calculate the Larmor frequency using the equation \omega _{\text {Larmor}}=\frac{\mu B}{\hbar}. Plugging in the known values, we get \omega _{\text {Larmor}}=\frac{eB}{2m_e}, which is the same as the equation given by hyperphysics.

For the allowed values of the magnetic energy, we can use the equation E=\mu B. Since the magnetic moment can have two possible values, the magnetic energy can also have two possible values: +\frac{e\hbar B}{4m_e} and -\frac{e\hbar B}{4m_e}. These are the allowed values of the magnetic energy for an electron in the n=2 state of a hydrogen atom in an external magnetic field of intensity B=1T.
 

Related to Calculate Larmor Freq. for Electron in n=2 of Hydrogen Atom

What is Larmor frequency?

Larmor frequency is the frequency at which a charged particle, such as an electron, precesses around a magnetic field. It is named after physicist Joseph Larmor, who first described this phenomenon.

How is Larmor frequency calculated?

The Larmor frequency can be calculated using the formula f = γB/2π, where f is the frequency, γ is the gyromagnetic ratio (a constant value for a given particle), and B is the strength of the magnetic field. For an electron in the n=2 energy level of a hydrogen atom, the gyromagnetic ratio is 1.760859x10^11 rad T^-1 s^-1.

Why is the Larmor frequency important?

The Larmor frequency is important in many areas of physics, including nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI), as it allows us to control and manipulate the behavior of charged particles in a magnetic field.

What is the significance of n=2 in the calculation of Larmor frequency for an electron in a hydrogen atom?

The energy level n=2 in a hydrogen atom is the first excited state, meaning that the electron in this state has a higher energy than the ground state. This higher energy results in a higher Larmor frequency compared to an electron in the ground state, which has an n=1 energy level.

Can the Larmor frequency be changed?

Yes, the Larmor frequency can be changed by altering the strength of the magnetic field. Additionally, different types of particles have different gyromagnetic ratios, leading to different Larmor frequencies. For example, the Larmor frequency for a proton is different from that of an electron in the same magnetic field.

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