Given that, initial kinetic energy of electrons, Ki=100‌eV Initial potential energy, Ui=0 Let Kf and Uf be final kinetic and potential energies, ∴ Kf=0 By using law of conservation of energy, Ki+Ui=Kf+Uf Uf=Ki ⇒Ki=Ui=
edσ
ε0
Now, substituting the values, we get 100×1.6×10−19=