An electron (mass m) with an initial velocity

 An electron (mass m) with an initial velocity  is in an electric field  . If λ0 = h/mv0, it’s de Broglie wavelength at time t is given by

(a) λ0

(b)

$\lambda_{0} \sqrt{1+\frac{e^{2} E_{0}^{2} t^{2}}{m^{2} v_{0}^{2}}}$

(c)

$\frac{\lambda_{0}}{\sqrt{1+\frac{e^{2} E_{0}^{2} t^{2}}{m^{2} v_{0}^{2}}}}$

(d)

$\frac{\lambda_{0}}{1+\frac{e^{2} E_{0}^{2} t^{2}}{m^{2} v_{0}^{2}}}$