An electron (charge = e, mass = m) is accelerated from rest through a potential difference of V volt. What will be the de Broglie wavelength of the electron?

Explanation

Kinetic energy gained by the electron
`= eV = (1)/(2) mv^(2) or, v = sqrt((2eV)/(m))`
Hence, de Broglie wavelength,
`lamda = (h)/(mv) = (h)/(m) sqrt((m)/(2eV)) = (h)/(sqrt(2meV))`