If each hydrogen atom is excited by giving $8.4 \ eV$ of energy,then the number of spectral lines emitted is equal to :

What is the wavenumber of the photon emitted during transition from the orbit $n=5$ to that of $n=2$ in hydrogen atom (in $cm^{-1}$)?
$\left[R_{H}=109677 \ cm^{-1}\right]$

An electron in a hydrogen atom in its ground state absorbs $2$ times as much energy as the minimum required for it to escape from the atom. The kinetic energy of the emitted electron is ............ $eV$.

The energy of the orbit of hydrogen is $E_n = \frac{1.31 \times 10^6}{n^2} \ J \ mol^{-1}$. If an electron transits from $n = 3$ to $n = 2$,find the frequency of the emitted radiation. (Note: $h = 6.6 \times 10^{-34} \ J \ s$,$N_A = 6.02 \times 10^{23} \ mol^{-1}$)

If $m$ and $e$ are the mass and charge of the revolving electron in the orbit of radius $r$ for a hydrogen atom,the total energy of the revolving electron will be:

Match the spectral lines given in List-$I$ with their corresponding lower energy transitions given in List-$II$.

List-$I$	List-$II$
$(1)$ Lyman	$(A)$ $n = 5 \to n = 4$
$(2)$ Paschen	$(B)$ $n = 3 \to n = 2$
$(3)$ Brackett	$(C)$ $n = 6 \to n = 5$
$(4)$ Balmer	$(D)$ $n = 4 \to n = 3$
	$(E)$ $n = 7 \to n = 6$