Heat treatment of muscular pain involves radiation of wavelength of about 900 nm. Which spectral line of H atom is suitable for this?
Given : Rydberg constant $\left. {{{\text{R}}_{\text{H}}}={{{10}}^{5}}~\text{c}{{\text{m}}^{{-1}}},~\text{h}=6.6\times {{{10}}^{{-34}}}~\text{J}~\text{s},\text{c}=3\times {{{10}}^{8}}~\text{m}/\text{s}} \right)$