Answer: 2.75×10^-7m
Explanation:
The work function refers to the smallest energy a photon must posses in order to cause the ejection of electrons from a metal surface.
If Eo= hfo
Eo=work function of the metal
fo=threshold frequency
h= Plank's constant
But Eo= hf= hc/wavelength
Wavelength= hc/Eo
We convert Eo to joules
4.50×1.6×10^-19=7.2×10^-19J
c=3×10^8ms-1
h=6.6×10^-34Js
Wavelength= 3×10^8×6.6×10^-34/7.2×10^-19
2.75×10^-7m
