Alight source of wavelength λ illuminates a metal and ejects photoelectrons with a maximum kinetic energy of 2.00 ev. a second light source with half the wavelength of the first ejects photoelectrons with a maximum kinetic energy of 6.00 ev. what is the work function of the metal?

Explanation:

Energy from a light source (photons):

E=h*c/λ

Photoelectric effect and Work function (W):

E=W+Ek

Ek: maximum kinetic energy from photoelectrons

then:

h*c/λ=W+Ek

Case 1:

 (1)

Case 2:

but  

 (2)

If we divide (2) by (1):

probably not if net force is zero

a lot of it means it can be "burned" for energy and sold at one price. if it is scarce, the price will go up