units for E=hv

[Jaden Haskins 2E]

Hi! When calculating E=hv, how do yo9u know if it is in J/photon or J/atom? I was doing some hw problems (1B #7 and 9) and one was in J/atom and the other was in J/photon, so I was wondering why you can do this and how to tell when to use which set of units.

[Akash J 1J]

Hi! When calculating E=hv, how do yo9u know if it is in J/photon or J/atom? I was doing some hw problems (1B #7 and 9) and one was in J/atom and the other was in J/photon, so I was wondering why you can do this and how to tell when to use which set of units.

I am not entirely sure, but whatever you end up with, it should be in Joules. So, if you are calculating the energy of a photon, you are going to end up with J/photon. I'm not sure where J/atom comes in, but in general you'll end up with J/(unit)

[Mikayla Kwok 3K]

I think E=hv is used for electromagnetic radiation, so it should be generally used with the units J/photon. However, if the problem makes a comment about one atom being associated with one photon, I think that's when you would use J/atom.

[CesarLec1]

It can be J/photon or J/atom, depends on the context and what the question is looking for.

[Olivia Monroy 1A]

By default I think we assume is it J/photon as that is what the energy equation is telling us, energy of incoming photon, but it could be J/atom I guess in another case, it would be made clear.

[Erika Sosa-Cruz 1J]

It depends on what the question is asking ( wording) however, I would think for the final he would want us to convert it to Joules.

[Morgan Gee 3B]

Using the equation E - hv, you get joules/photon. This allows us to calculate the amount of joules per mol and other similar units using dimensional analysis.

[805593945]

E=hv is specifically for photon/radiation so it'll be J/photon.

[David Liu 1E]

I think it's normally j/photon, but you would check with the question to make sure because sometimes it can change to j/atom

[Diana Aguilar 3H]

I thinks it's mostly going to be j/photon, but it can also be j/atom, it really depends on the question.

[Joshua Swift]

Depending on the question, the units can either be J/photon or J/atom.

[Mauricio Maravilla 3C]

Joules per photon would be if the question is talking about an incoming light source and joules per atom probably refers to the energy released by each atom when light excites it. Hope this helped

[joshua_quinn_1C]

Hello! The units depend on what the question is asking for and the context of the scenario as well. However, most of the time the units will most likely be J/photon since we are using this equation to find the energy of the photon during the photoelectric effect.

[Tracy Tran 3L]

I thinks it's mostly going to be j/photon, but it can also be j/atom, it really depends on the question.

If we are expected to find J/Photon would any additional calculations need to be made or would we just need to change the units?

[Rainy Liu Ruoshui_2K]

Because E=hv is applied to photoelectric effects, v is the frequency of the light. Thus, the unit should be E/photon but not E/atom.

[Divya Mehta 2K]

The answer should be given in joules, and since we are dealing with photoelectric particles, it would usually be in joules/photon or joules/atom

[Jiayin Yola Yan 1G]

Jules. Because energy always ends in Jules and the units of v and h cancels out, leaving only the J.

[Arden Napoli 1E]

I think the units in this case depends on how the question is worded and the values that are given to you in the context of the problem. For instance if moles are mentioned in the wording of the question, it will most likely be J/atoms, but I think usually the units are J/photon if there is not an explicit mentioning of something other than photon.

[Ashley Johnson 2G]

Would the use of photon or atom depend on what you need to cancel out in order to end the problem with J?

[Madison Yee 2B]

Generally, E=hv is referring to the joules of energy per photon. However, depending on the problem at hand, you can use this information to calculate values such as the energy of the electrons emitted.

[Alessandra Marotta 3L]

As others have stated, I believe it is dependent on the what the question is asking for. Some questions are asking about calculating the energy of a photon, so in that case the units would be J/photon. It can be J/atom if the question is specifically asking about atoms, but I think it is typically J/photon.

[William Huang 1K]

For the equation in particular you are finding the J/photon but in E = hv - phi or other variants it could change because the latter equation is the kinetic energy of the electron that is ejected.