Under what potential difference should an electron be accelerated to obtain electron waves of `lamda = 0.6 Å`? Given, mass of electron, `m = 9.1 xx 10^(-31) kg`, Planck's constant, `h = 6.62 xx 10^(-34) J.s`

Explanation

We know, `lamda = (h)/(mv), (1)/(2) mv^(2) = eV`
`:. mv = sqrt(2meV) or, lamda = (h)/(sqrt(2meV))`
or, `lamda^(2) = (h^(2))/(2meV) or, V = ((h)/(lamda))^(2).(1)/(2me)`
`:. V = ((6.62 xx 10^(-34))/(0.6 xx 10^(-10)))^(2) xx (1)/(2 xx 9.1 xx 10^(-31) xx 1.6 xx 10^(-19))`
= 418.04 V