Question

White light, with frequencies ranging from 4.00×1014Hz to 7.90×1014Hz, is incident on a barium surface. Given that the work function of barium is 2.52 eV, find the maximum kinetic energy of electrons ejected from this surface. Given that the work function of barium is 2.52 eV, find the range of frequencies for which no electrons are ejected.

Answer 1

ans =6.081X10 14 Hz

No electrons injected = 0K.E

1eV=1.6×10^-19J

h=6.63 x 10^-34js

Wo=2.52 eV / 4.032x10 -19 J

fo = ?

Wo= h fo

(6.63 x 10 - 34) fo = 4.032 x 10-19

fo = 4.032 X 10-19/6.63x10-34

fo = 6.081X10 14 Hz