The energy of a hydrogen atom in the $n^{th}$ orbit is $E_n$. What will be the energy in the $n^{th}$ orbit of a singly ionized helium atom?

According to the Bohr atom model,in which of the following transitions will the frequency be maximum?

The energy levels of a hydrogen atom are shown below. The transition corresponding to the emission of the shortest wavelength is

For a certain hypothetical one-electron atom,the wavelength (in $\mathring{A}$) for the spectral lines for transition from $n = p$ to $n = 1$ is given by $\lambda = \frac{1500p^2}{p^2 - 1}$ (where $p > 1$). The ionization potential of this element must be ......$V$ (Take $hc = 12420 \text{ eV-} \mathring{A}$).

If energy of $15 \ eV$ is given to an electron in the $4^{th}$ orbit,find its final energy when it comes out of the $H$-atom. (in $eV$)

An electron makes a transition from an excited state to the ground state of a hydrogen-like atom. Out of the following statements,which one is correct?