II. Explaining photoelectric effect using quantum theory

A. Quantum theory

1) electrons can only absorb or emit energy in discrete amounts called quanta (packets)

 

2) Energy of each quanta (photon) is proportional to frequency of radiation

h = Planck's constant =

6.63 X 10^-34 Js

Since: c = fλ

c = 3 x 10⁸ m/s

And f = c/λ

Einstein, photoelectric effect