Question

Upon being struck by 240-nm photons, a metal ejects electrons with a maximum kinetic energy of 1.45 eV. What is the work function of this metal? (A) 3.73 eV (B) 3.13 eV (C) 4.33 eV (D) 4.92 eV

Answer 1

Answer:

W = 3.73 eV

Explanation:

Given data:

wavelength of photons 240 nm

kinetic energy 1.45 eV

B y using photoelectric equation

Kinetic Energy  =  Photon Energy - work friction

$K.E = \frac{hc}{\lambda} -W$

$\frac{hc}{\lambda} = \frac{6.63\times 10^{-34}\times 3\times 10^8}{240\times 10^{-9}\times 1.6\times 10^{-19}} eV$

                              = 5.179 eV

                              = 5.18 eV$W = \frac{hc}{\lambda} - K.E$

    = (5.18 - 1.45) eV

W = 3.73 eV