Light Intensity and Photons


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Lorraine Medina 3E
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Light Intensity and Photons

Postby Lorraine Medina 3E » Wed Oct 14, 2020 11:02 pm

Why does increasing light intensity increase the number of photons?

Madilyn Schindler 3E
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Re: Light Intensity and Photons

Postby Madilyn Schindler 3E » Wed Oct 14, 2020 11:25 pm

Intensity is defined as the total amount of energy going through a unit area per unit time. Therefore, the two ways of increasing intensity are by either increasing the number of photons, or increasing the amount of energy in each individual photon. Hope that helps!

Megan Singer 3D
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Re: Light Intensity and Photons

Postby Megan Singer 3D » Wed Oct 14, 2020 11:36 pm

Actually, I'm pretty sure that using the particle model, the only way to increase the intensity is to increase the number of photons (this makes sense to me when I think about how light with more intensity is brighter, i.e. there is more light). Increasing the amount of energy of each photon just changes the type of light it is, not its intensity. For example, UV light has more energy/a higher frequency/a shorter wavelength than visible light. (All of these are related through the E=hν and λν = c equations) When looking at the wave model, you can increase intensity by increasing the amplitude of the wave. Increasing the amplitude does not change wavelength or frequency so you would still have the same type of light, just at a different intensity.

Katie Le 3K
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Re: Light Intensity and Photons

Postby Katie Le 3K » Thu Oct 15, 2020 12:05 am

Intensity is in simpler terms the number of photons in light. so increasing intensity means adding more photons

Binyu You
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Re: Light Intensity and Photons

Postby Binyu You » Thu Oct 15, 2020 7:08 am

Intensity is the amplitude of light, and it is the total amount of energy going through every time. I believe the way to increase intensity is to increase photon number.

Pranav Daggubati 3C
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Re: Light Intensity and Photons

Postby Pranav Daggubati 3C » Thu Oct 15, 2020 9:36 am

Intensity depends on the number of photons because it is a measure of how many photons are passing through an area at a certain time.

Brandon Le 3C
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Re: Light Intensity and Photons

Postby Brandon Le 3C » Thu Oct 15, 2020 11:36 pm

Light intensity can be defined as photon energy per second per unit area. The intensity of light is also designated by the amplitude of the wave model. Therefore, increasing the number of photons would increase the intensity of the light, but the wavelength and frequency would remain the same, since the amplitude does not affect these two aspects of the wave model.

Chris_Butler_1A
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Re: Light Intensity and Photons

Postby Chris_Butler_1A » Fri Oct 16, 2020 10:26 am

Brandon Le 3C wrote:Light intensity can be defined as photon energy per second per unit area. The intensity of light is also designated by the amplitude of the wave model. Therefore, increasing the number of photons would increase the intensity of the light, but the wavelength and frequency would remain the same since the amplitude does not affect these two aspects of the wave model.

If I can ask, I was a little confused about how the amplitude of the wave works. For example, if we increased the amplitude what would happen to the wave, or what would we see in a theoretical experiment?

Chem_Mod
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Re: Light Intensity and Photons

Postby Chem_Mod » Fri Oct 16, 2020 10:31 am

Chris_Butler_1A wrote:
Brandon Le 3C wrote:Light intensity can be defined as photon energy per second per unit area. The intensity of light is also designated by the amplitude of the wave model. Therefore, increasing the number of photons would increase the intensity of the light, but the wavelength and frequency would remain the same since the amplitude does not affect these two aspects of the wave model.

If I can ask, I was a little confused about how the amplitude of the wave works. For example, if we increased the amplitude what would happen to the wave, or what would we see in a theoretical experiment?

When you increase the amplitude of the wave, you are essentially just changing the height of the peak of a wave. However, as the last student stated, the wavelength or frequency is not affected, because only the vertical height of the peak is being changed. If you draw this out, you would see that the "horizontal" would not be affected, and so wavelength and frequency are also unaffected.


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