# What determines if the photoelectric effect occurs?

1. Aug 8, 2011

### MRFISCHERRULZ

What determines if the photoelectric effect occurs?
There are several aspects on this topic that I don't really understand such as:

- What is the relationship between the frequency of the incident photon, threshold frequency and the ejection of electrons?

- What is the relationship between the energy of the incident photon, the work function and the ejection of electrons?

- What is the relationship between kinetic energy of the ejected electrons, the energy of the incident photon and the work function?

- What is the relationship between the intensity of the incident light and the average kinetic energy of the ejected electrons?

- What is the relationship between the intensity of the incident light and the number of ejected electrons?

Thanks

2. Aug 8, 2011

### MRFISCHERRULZ

Forgot to include my work so far, please assist me if this is correct so far, thanks

1)The energy of a photon is a function of the frequency of the photon

Energy = (Planck's constant * Speed of Light) / wavelength = Planck's Constant * Frequency

If energy is large enough it will knock an electron loose

2) Any energy in excess of what is needed to knock an electron loose (Work Function) goes to KE of the electron

4) Not related the number of photons per second has no relationship to the KE of the ejected electrons

5) The more high energy photons you have the more electrons you knock loose

3. Aug 8, 2011

### cepheid

Staff Emeritus
For 1 you haven't addresses threshold frequency.