The recoil speed of a hydrogen atom after it emits a photon in going from $n = 5$ state to $n = 1$ state will be ..... $m/s$.

An electron jumps from the $4th$ orbit to the $2nd$ orbit of a hydrogen atom. Given the Rydberg constant $R = 10^5 \text{ cm}^{-1}$. The frequency in $\text{Hz}$ of the emitted radiation will be:

$A$ hydrogen atom falls from $n^{\text{th}}$ higher energy orbit to the first energy orbit $(n=1)$. The energy released is equal to $12.75 \text{ eV}$. The $n^{\text{th}}$ orbit is:

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

What is the ground state of an atom? And what is the ionization energy and excitation energy of a hydrogen atom?

In a hydrogen-like atom,when an electron jumps from the $M$-shell to the $L$-shell,the wavelength of the emitted radiation is $\lambda$. If an electron jumps from the $N$-shell to the $L$-shell,the wavelength of the emitted radiation will be: