Show that the ratio of the magnetic dipole moment to the angular momentum

Question: Show that the ratio of the magnetic dipole moment to the angular momentum $\mathrm{I}=\mathrm{mvr}$ is a universal constant for hydrogen like atoms and ions. Find its value. Solution:...

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Calculate the magnetic dipole moment corresponding to the motion

Question: Calculate the magnetic dipole moment corresponding to the motion of the electron in the ground state of a hydrogen atom. Solution:...

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Average lifetime of a hydrogen atom excited to n=2 state is

Question: Average lifetime of a hydrogen atom excited to $n=2$ state is $10^{-8} \mathrm{~s}$. Find the number of revolutions made by the electron on the average before it jumps to the ground state. Solution:...

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Solve this following

Question: Mark $(\sqrt{ })$ against the correct answer in the following:. $f(x)=\frac{2 x}{\log x}$ is increasing in A. $(0,1)$ B. $(1, \mathrm{e})$ C. $(e, \infty)$ D. $(-\infty$, e $)$ Solution:...

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Find the temperature at which the average thermal kinetic energy is equal

Question: Find the temperature at which the average thermal kinetic energy is equal to the energy needed to take a hydrogen atom from its ground state to $\mathrm{n}=3$ state. Hydrogen can now emit red light of wavelength $653.1 \mathrm{~nm}$. Because of Maxwellian distribution of speeds, a hydrogen sample emits red light at temperatures much lower than that obtained from this problem. Assume that hydrogen molecules dissociate into atoms. Solution:...

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The average kinetic energy of molecules in a gas at temperature

Question: The average kinetic energy of molecules in a gas at temperature $t$ is $1.5 \mathrm{kT}$. Find the temperature at which the average kinetic energy of the molecules of hydrogen equals the binding energy of its atoms. Will hydrogen remain in molecular form at this temperature? Take $\mathrm{k}=8.62 \times 10^{-6} \mathrm{eV} / \mathrm{K}$. Solution:...

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According to Maxwell's theory of electrodynamics,

Question: According to Maxwell's theory of electrodynamics, an electron going in a circle should emit radiation of frequency equal to its frequency of revolution. What should be the wavelength of the radiation emitted by a hydrogen atom in ground state if this rule is followed? Solution:...

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Suppose, in certain conditions only those transitions are allowed to hydrogen atoms in

Question: Suppose, in certain conditions only those transitions are allowed to hydrogen atoms in which the principal quantum number $\mathrm{n}$ changes by 2 . Find the smallest wavelength emitted by hydrogen. List the wavelength emitted by hydrogen in the visible range ( $380 \mathrm{~nm}$ to $780 \mathrm{~nm})$. Solution:...

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A spectroscopic instrument can resolve two nearby wavelength

Question: A spectroscopic instrument can resolve two nearby wavelength $\lambda$ and $\lambda+\Delta \lambda$ if $\lambda / \Delta \lambda$ is smaller than 8000 . This is used to study the spectral lines of the Balmer series of hydrogen. Approximately how many lines will be resolved by the instrument? Solution:...

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Find the maximum angular speed of the electron of a hydrogen atom in a stationary orbit.

Question: Find the maximum angular speed of the electron of a hydrogen atom in a stationary orbit. Solution:...

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A gas of hydrogen like ions is prepared in a particular excited state A.

Question: A gas of hydrogen like ions is prepared in a particular excited state A. It emits photons having wavelength equal to the wavelength of the first line of Lyman series together with photons of five other wavelengths. Identify the gas and find the principal quantum number of the state A. Solution:...

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A hot gas emits radiation of wavelengths 46.0 nm,

Question: A hot gas emits radiation of wavelengths $46.0 \mathrm{~nm}, 82.8 \mathrm{~nm}$ and $103.5 \mathrm{~nm}$ only. Assume that the atoms have only two excited states and the difference between consecutive energy levels decreases as energy is increased. Taking the energy of the highest energy state to be zero, find the energies of the ground state and the first excited state. Solution:...

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What is the energy of a hydrogen atom in the first excited state

Question: What is the energy of a hydrogen atom in the first excited state if the potential energy is taken to be zero in the ground state? Solution:...

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A hydrogen atom in state n=6 makes two successive transitions and reaches the ground state.

Question: A hydrogen atom in state $n=6$ makes two successive transitions and reaches the ground state. In the first transition a photon of $1.13 \mathrm{eV}$ is emitted. Find the energy of the photon emitted in the second transition. What is the value of $\mathrm{n}$ in the intermediate state? Solution:...

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Whenever a photon is emitted by hydrogen in Balmer series,

Question: Whenever a photon is emitted by hydrogen in Balmer series, it is followed by another photon in Lyman series. What wavelength does this latter photon correspond to? Solution:...

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A hydrogen atom in a state having a binding energy of

Question: A hydrogen atom in a state having a binding energy of $0.85 \mathrm{eV}$ makes transition to a state with excitation energy $10.2 \mathrm{eV}$. Identify the quantum numbers $n$ of the upper and the lower energy states involved in the transition. Find the wavelength of the emitted radiation. Solution:...

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Find the maximum Coulomb force that can act on the electron due to the nucleus in a hydrogen atom.

Question: Find the maximum Coulomb force that can act on the electron due to the nucleus in a hydrogen atom. Solution:...

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A positive ion having just one electron ejects it if a photon of wavelength

Question: A positive ion having just one electron ejects it if a photon of wavelength $228 \mathrm{~A}^{\circ}$ or less is absorbed by it. Identify the ion. Solution:...

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Solve this following

Question: Mark $(\sqrt{)})$ against the correct answer in the following: $f(x)=\sin x$ is increasing in A. $\left(\frac{\pi}{2}, \pi\right)$ B. $\left(\pi, \frac{3 \pi}{2}\right)$ C. $(0, \pi)$ D. $\left(\frac{-\pi}{2}, \frac{\pi}{2}\right)$ Solution:...

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A group of hydrogen atoms are prepared in n=4 states.

Question: A group of hydrogen atoms are prepared in $n=4$ states. List the wavelength that are emitted as the atoms make transition and return to $\mathrm{n}=2$ states. Solution:...

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Find the first excitation potential of He+ion.

Question: Find the first excitation potential of $\mathrm{He}^{+}$ion. Find the ionization potential of $\mathrm{Li}^{++}$ion. Solution:...

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A hydrogen atom emits ultraviolet radiation of wavelength

Question: A hydrogen atom emits ultraviolet radiation of wavelength $102.5 \mathrm{~nm}$. What are the quantum numbers of the states involved in the transition? Solution:...

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Find the radius and energy of a He+ ion in the state n=2.

Question: Find the radius and energy of $\mathrm{He}^{+}$ion in the state $\mathrm{n}=2$. Solution:...

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Find the binding energy of a hydrogen atom in the state n=2.

Question: Find the binding energy of a hydrogen atom in the state $n=2$. Solution:...

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Evaluate Rydberg constant by putting the values of the fundamental

Question: Evaluate Rydberg constant by putting the values of the fundamental constants in its expression. Solution:...

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