units for E=hv


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Jaden Haskins 2E
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units for E=hv

Postby Jaden Haskins 2E » Fri Dec 11, 2020 10:42 am

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
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Re: units for E=hv

Postby Akash J 1J » Fri Dec 11, 2020 11:13 am

Jaden Haskins 2F wrote: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
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Re: units for E=hv

Postby Mikayla Kwok 3K » Fri Dec 11, 2020 4:06 pm

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
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Re: units for E=hv

Postby CesarLec1 » Fri Dec 11, 2020 11:03 pm

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

Olivia Monroy 1A
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Re: units for E=hv

Postby Olivia Monroy 1A » Fri Dec 11, 2020 11:06 pm

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
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Re: units for E=hv

Postby Erika Sosa-Cruz 1J » Sat Dec 12, 2020 10:41 am

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
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Re: units for E=hv

Postby Morgan Gee 3B » Wed Dec 16, 2020 7:29 am

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
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Re: units for E=hv

Postby 805593945 » Wed Dec 16, 2020 8:31 am

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

David Liu 1E
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Re: units for E=hv

Postby David Liu 1E » Wed Dec 16, 2020 2:12 pm

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
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Re: units for E=hv

Postby Diana Aguilar 3H » Wed Dec 16, 2020 6:16 pm

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
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Re: units for E=hv

Postby Joshua Swift » Wed Dec 16, 2020 6:47 pm

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

Mauricio Maravilla 3C
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Re: units for E=hv

Postby Mauricio Maravilla 3C » Wed Dec 16, 2020 9:46 pm

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


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