Calculate the wavelength of a photon in Angstrons having an energy of 1 electron-volt.

Explanation

Energy (E) = 1EV = `1.602 xx 10^(-19)J`
`h = 6.626 xx 10^(-34) Js, c = 3 xx 10^(8) ms^(-1)`
`E = hv = (hc)/(lamda)`
or `lamda = (hc)/(E) = ((6.626 xx 10^(-34) Js) (3 xx 10^(8) ms^(-1)))/(1.602 xx 10^(-19) J) = 12.42 xx 10^(-7) m`
`= 12.42 xx 10^(-7) xx 10^(10) Å = 12.42 xx 10^(3) Å`