The photoelectric effect Flashcards
What is the photoelectric effect?
The photoelectric effect is the process of a photon of a certain quantized energy being absorbed by an electron allowing it to be emitted from a metal
What effect would increasing the intensity of the light have on the photoelectric effect?
It would cause more electrons to be released
What effect does increasing the frequency of the incoming light wave do to the photoelectric effect
The frequency of released electrons would stay the same but the kinetic energy of the electrons being released would be higher
What is an electron volt?
An electron volt (eV) is the work done moving an electron through a potential difference of 1V and so 1eV = 1.6x10^-19J, which is the same value as the elementary charge. This is because W=VQ and Q in this case is the charge on an electron so e, and V=1V, so W=e
What is the work function of a material?
The work function, ϕ, of a material is a property that defines the minimum energy needed to release and electron from the surface of a material
How would you find the maximum kinetic energy of an emitted electron?
Ek (Max) = hf - ϕ, meaning the total energy from the photon minus the work function energy
What is the threshold frequency?
The threshold frequency is the minimum frequency needed for the photon to have the same energy as the work function meaning the minimum frequency the light needs to have to release an electron from the surface of a metal. This means ϕ = hf where f is the threshold frequency
What is the threshold wavelength?
The maximum wavelength needed to release an electron from the surface of a metal, meaning ϕ=(hc)/λ
