## photons

EMurphy_2L
Posts: 128
Joined: Sat Sep 07, 2019 12:16 am

### photons

does a short wavelength = more energy per photon? or is wavelength intensity??
also, is intensity proportional to electrons emitted (only if able to remove electron already) like doubled intensity results in doubled amount of electrons emitted?

MingdaH 3B
Posts: 133
Joined: Thu Jul 11, 2019 12:17 am

### Re: photons

A shorter wavelength or higher frequency = more energy. Intensity has nothing to do with the energy of the photon, but rather, it has to do with the amplitude of the wave which corresponds to the "number" of photons

Rodrigo2J
Posts: 102
Joined: Sat Jul 20, 2019 12:16 am

### Re: photons

If you were to look at the formula for finding the energy of a photon we see that E=hc/lambda. We see from the equation that frequency and Energy per photon have an inverse relationship. If the frequency gets smaller, the energy per photon gets larger. If frequency gets bigger, energy per photon gets smaller.
As for your second question, intensity only increases the number of photons and doesn't have an effect on the frequency. If threshold energy is reached, however, and electrons can be emitted, doubling the intensity (doubling the number of photons interacting with electrons 1 to 1) would result in subsequent interactions between each photon and electron. So, simply, I think doubling the intensity (if threshold energy is already reached) would also result in an increase of electrons released.

sarahsalama2E
Posts: 164
Joined: Fri Aug 30, 2019 12:16 am

### Re: photons

Yes, as mentioned above intensity is NOT the determining factor as to whether or not electrons will be ejected from a given material, but it is rather the frequency as the frequency is the determinant of whether or not the threshold energy, or the work function will be met which is needed to eject electrons from a metal. Yes, and to answer your question if the frequency is met THEN intensity will double the amount of electrons ejected. It is key to understand that the frequency value first must be met or exceeded to eject an electron.