SOLUTION : For the Balmer series of the hydrogen atom
$\bar{v}=\frac{1}{\lambda}=R_{H}\left(\frac{1}{2^{2}}-\frac{1}{n^{2}}\right)$
Shortest wavelength means that radiation is of highest energy, hence $n=\infty$.
$\bar{v}=109677 \times \frac{1}{4} cm ^{-1}=27419 \cdot 25 cm ^{-1} \text {. }$