When hydrogen is bombared by 10.2 eV and 12.1 eV electrons, in Frank Hertz, experiment, emission of

Question

When hydrogen is bombared by 10.2 eV and 12.1 eV electrons, in Frank Hertz, experiment, emission of the three spectral lines was observed. The wavelength corresponding to 10.2 eV is\

Professor PC Thomas Classes · Answer

$\frac{\mathrm{hc}}{\lambda}=\mathrm{E}$                $\mathrm{E}=10.2 \mathrm{eV}=10.2 	imes 1.6 	imes 10^{-19} \mathrm{~J}$
$\lambda=\frac{h c}{E}$                 $\mathrm{h}=6.6 	imes 10^{-34} \mathrm{Js}$
$$
\mathrm{c}=3 	imes 10^{8} \mathrm{~m} / \mathrm{s}
$$
$=\mathrm{m}$
$=\AA$