The work function of a metal is 2.56 x 10-19J. Calculate the frequency of a photon whose energy is required to eject from the metal an electron with kinetic energy of 3.0ev. [1 eV = 1.6 x 10-19J, h = 6.6 x 10-34Js]
-
A.
5.56 x 1019Hz -
B.
1.66 x 1019Hz -
C.
1.12 x 1015Hz -
D.
8.42 x 1014Hz
Correct Answer: Option C
Explanation
F = (frac{K.E + Wo}{h})
= (frac{3.0 times 1.6 times 10^{-19} + 2.56 times 106{-19}}{6.6 times 106{-34}})
– 1.12 x 10-15HZ