Question

in his explanation of the threshold frequency in the photoelectric effect, Einstein reasoned that the absorbed photon must have a minimum energy to dislodge an electron from the metal surface. This energy is called the work function of that metal. What is the longest wavelength of radiation (in nm) that could cause the photoelectric effect in each of these metals: (a) calcium, work function = 4.60x10^-19J; (b) titanium, work function =6.94x 10^-19J; (c) sodium, work function = 4.41x 10^-19J

Answer 1

Use plancks equation to find a wavelength of a photon of those energies.

\(E_{photon}=\dfrac{h*c}{\lambda}\)

h=plancks constant
c=speed of light

Answer 2

Thank you, this helped out!