The energy required for the ionisation of a certain atom is $3.44\times10^{-18}J$. The absorption of a photon of unknown wavelength ionises the atom and ejects an electron with velocity $1.03\times10^6$ m/sec. Calculate the wavelength of the incident radiation.

Question

$(a)\;68.73nm\qquad(b)\;50.71nm\qquad(c)\;47nm\qquad(d)\;52.3nm$