Explanation

(c) According to the Bohr’s theory the wavelength of radiations emitted from hydrogen atom given by
$\ \ \ \ \ \ \ \ \ \ \ \ \ \frac{1}{\lambda} =$ $R\left\lbrack \frac{1}{n_{1}^{2}} - \frac{1}{n_{2}^{2}} \right\rbrack \Rightarrow \lambda = \frac{n_{1}^{2}n_{2}^{2}}{\left( n_{2}^{2}n_{1}^{2} \right)R}$
For maximum wavelength if$n_{1} = n,$then $n_{2} = n + 1$
$\therefore\ \lambda\ is\ maximumforn_{2} = 3\ and\ n_{1} = 2.$