Given the value of Rydberg constants is ${\rm{1}}{{\rm{0}}^7}\,{{\rm{m}}^{ - 1}}$, the wave number of the last line of the Balmer series in hydrogen spectrum will be:

The ratio of the kinetic energy to the total energy of an electron in a Bohr orbit is

According to Bohr's model, the angular momentum of an electron in the $n^{th}$ orbit is quantized and proportional to:

The ionisation energy of ${\rm{10 }}\,{\rm{times}}$ ionised sodium atom is

In a hydrogen atom, an electron resides in the nth Bohr orbit. What is the ratio of its kinetic energy to its potential energy?

If the radius of the first Bohr orbit of a hydrogen atom is $5.3 imes 10^{-11}$ m, what is the radius of the fourth allowed orbit?

If the kinetic energy of an electron in an atom is $10.2$ eV and its potential energy is $-20.4$ eV, what is its total energy?

The radius of electron’s second stationary orbit in Bohr’s atom is $R$. The radius of the third orbit will be

Given the value of Rydberg constants is ${\rm{1}}{{\rm{0}}^7}\,{{\rm{m}}^{ - 1}}$, the wave number of the last line of the Balmer series in hydrogen spectrum will be:

Which of the relation is correct between time period and number of orbits while an electron is revolving in an orbit

In Bohr's model, the radius of the nth orbit is proportional to: