Questions in atomic-structure

Select	Question
	The frequency corresponding to transition $n = 2$ to $n = 1$ in hydrogen atom is
	The mass of a photon with a wavelength equal to $1.54 \times {10^{ - 8}}cm$ is
	Splitting of spectral lines under the influence of magnetic field is called
	The radius of electron in the first excited state of hydrogen atom is
	The ratio of area covered by second orbital to the first orbital is
	Time taken for an electron to complete one revolution in the Bohr orbit of hydrogen atom is
	The radius of which of the following orbit is same as that of the first Bohr's orbit of hydrogen atom
	The frequency of radiation emitted when the electron falls from $n = 4$ to $n = 1$ in a hydrogen atom will be (Given ionization energy of H$ = 2.18 \times {10^{ - 18}}J\,\,\,{\rm{ato}}{{\rm{m}}^{ - 1}}$and $h = 6.625 \times {10^{ - 34}}Js$)
	The wavelength of the radiation emitted, when in a hydrogen atom electron falls from infinity to stationary state 1, would be (Rydberg constant $ = \,1.097\, \times \,{10^7}{m^{ - 1}}$)
	In Bohr’s model, atomic radius of the first orbit is $\gamma $, the radius of the $3rd$ orbit, is