An electron of mass ' m ' with an initial velocity v = v_0 i ( v_0>0) enters an electric field E =- E_o k. If the initial de Broglie wavelength is…

An electron of mass ' m ' with an initial velocity $\displaystyle \overrightarrow{\mathrm{v}}=\mathrm{v}_0 \hat{i}\left(\mathrm{v}_0>0\right)$ enters an electric field $\displaystyle \overrightarrow{\mathrm{E}}=-\mathrm{E}_{\mathrm{o}} \hat{\mathrm{k}}$. If the initial de Broglie wavelength is $\displaystyle \lambda_0$, the value after time t would be