List of top Physics Questions on Atoms

If the 9546 $\AA$ wavelength spectral line in hydrogen spectrum is due to the transition of an electron from a higher orbit to $n^{th}$ lower orbit, then the value of $n$ is:

Ratio of wavelengths of first and third Lyman spectral lines of hydrogen atom is:

The radius of second orbit of hydrogen atom is 2.12 Å and the velocity of the electron revolving in this orbit is $1.1\times10^6 ms^{-1}$. According to classical electromagnetic theory, the initial frequency of light emitted by this electron is nearly}

The nuclides of $^{197}_{79}\mathrm{Au}$ and $^{196}_{80}\mathrm{Hg}$ are called ______ of each other

State Bohr’s postulates and derive the expression for the radius of the $ n^{\text{th}} $ orbit.

An electron moves in Bohr orbit. The magnetic field at the centre is proportional to

The maximum wavelength of incident radiation required to ionize a hydrogen atom in its ground state is nearly

The potential energy of an electron in an orbit of hydrogen atom is -6.8 eV. The de Broglie wavelength of the electron in this orbit is ($r_0$ is Bohr radius)

If the potential energy of an electron in an orbit of hydrogen atom is $-6.80$ eV, then the energy required to ionize the atom is

The distance of closest approach of an alpha particle from a nucleus when the alpha particle moves towards a nucleus with a kinetic energy 'E' is 'x'. The distance of closest approach when the alpha particle approaches the same nucleus with kinetic energy 0.4E is

The ratio of frequencies of second line of Lyman series and third line of Balmer series of hydrogen atom is:

The ratio of wavelengths of second line in Balmer series and the first line in Lyman series of hydrogen atom is

Prove that, in the Bohr model of the hydrogen atom, the time period of revolution of an electron in the $ n $-th orbit is proportional to $ n^3 $.

Assertion (A): The potential energy of an electron revolving in any stationary orbit in a hydrogen atom is positive.
Reason (R): The total energy of a charged particle is always positive.

The spectral series which corresponds to the electronic transition from the levels n₂ = 5, 6,… to the level n₁= 4 is

In hydrogen like system the ratio of coulombian force and gravitational force between an electron and a proton is in the order of:

The radius of the third stationary orbit of an electron in Bohr's atom is $ R $. The radius of the fourth stationary orbit will be:

A hydrogen atom in ground state is given an energy of 10.2 eV. How many spectral lines will be emitted due to transition of electrons ?

The ratio of the shortest wavelength of Balmer series to the shortest wavelength of Lyman series for hydrogen atom is :

If the wavelength of the first member of the Lyman series of hydrogen is $ \lambda $. The wavelength of the second member will be:

If Rydberg’s constant is $ R $, the longest wavelength of radiation in Paschen series will be $ \frac{\alpha}{7R} $, where $ \alpha = \_\_\_\_\_\_\_ $.

(a) "EM wavelength correlates with the size of the radiating system." Give two examples.
(i) Why do long-distance radio broadcasts use shortwave bands?
(ii) Why are X-ray telescopes satellite-based, while optical/radio telescopes are ground-based?

In the Balmer series of the hydrogen atom, as the wavelength of spectral lines decreases, they appear:

The radius $ r_n $ of the $ n^{th} $ orbit in the Bohr model of the hydrogen atom varies with $ n $ as:

The radius of innermost orbit of a hydrogen atom is 5.3x10^-11 m. What is the radius of the third allowed orbit of the hydrogen atom?