Question

Find out velocity of electron so that its momentum is equal to that of photon with a wavelength $\lambda =52000\mathring{A}$

Answer 1

Using $\lambda =\frac{h}{mv}$

Or $52000\times {10}^{-10}=\frac{6.6\times {10}^{-34}}{9.1\times {10}^{-31}\times v}$

$⟹v=139m/s$