Question

Calculate the accelerating potential that must be imparted to a proton beam to give it an effective wavelength of $0.005atm$.

Answer 1

$Energy=e\times v=\frac{hc}{\lambda }$

$e\times v=\frac{2\times {10}^{-25}}{.005},e=1.6\times {10}^{19}$

after putting the value of e in the above formula

$v=2.5\times {10}^{-4}$