A stream of electrons from a heated filament was passed

Question:

A stream of electrons from a heated filament was passed between two charged plates kept at a potential difference $\mathrm{V}$ esu. If $\mathrm{e}$ and $\mathrm{m}$ are charge and mass of an electron respectively, then the value of $\mathrm{h} / \lambda$ (where $\lambda$ is wavelength associated with electron wave) is given by :

  1. $\sqrt{2 \mathrm{meV}}$

  2. $\mathrm{meV}$

  3. $2 \mathrm{meV}$

  4. $\sqrt{\mathrm{meV}}$


Correct Option: 1

Solution:

$\therefore \frac{\mathrm{h}}{\lambda}=\sqrt{2 \mathrm{meV}}$

Leave a comment