The wavelength of an electron is obtained from de-Broglie equation.\\\\(\\displaystyle \\lambda = \\frac {h}{mv}\\\\) \\\\( = \\dfrac {6.626 \ imes 10^{-34} Js}{9.11 \ imes 10^{-31} kg\ imes 2.05 \ imes 10^{7} m/s}\\\\) \\\\(=3.55 \ imes 10^{-11}m \\\\)