Energy of light, light wavelength frequency relationship

Author: kevinlinxc

README.md

@@ -69,6 +69,5 @@ Then, repeat everything after step 5.
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-kevinlinxc: 37 formulas
+kevinlinxc: 39 formulas
 
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content/formulas/energy-of-light/index.md

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+---
+title: Photon Energy
+description: "The energy of a photon."
+summary: "The energy of a photon."
+tags: ["physics", "optics"]
+date: 2023-03-24
+latex: E = hf
+---
+
+{{< katex >}}
+
+The energy of a photon is:
+
+$$ E = hf = \frac{hc}{\lambda}$$
+
+Where
+
+* \\(h\\) is the [Planck constant](https://en.wikipedia.org/wiki/Planck_constant),
+* \\(f\\) is the frequency of the photon
+* \\(c\\) is the speed of light in a vacuum, and
+* \\(\lambda\\) is the wavelength of the light.
+
+## Sources
+
+- [Wikipedia](https://en.wikipedia.org/wiki/Photon_energy)
+- [Khan Academy](https://www.khanacademy.org/science/physics/quantum-physics/photons/v/photon-energy)
+
+## See also
+
+- [Light Wavelength and Frequency Relationship](/formulas/light-wavelength-frequency/)

content/formulas/light-wavelength-frequency/index.md

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+---
+title: "Light Wavelength and Frequency Relationship"
+description: "The relationship between the wavelength and frequency of light."
+summary: "The relationship between the wavelength and frequency of light."
+tags: ["physics", "optics"]
+date: 2023-03-24
+latex: c = \lambda f
+---
+
+{{< katex >}}
+
+The relationship between the wavelength and frequency of light in a vacuum is:
+
+$$ c_0 = \lambda f $$
+
+Where
+
+* \\(\scriptsize \lambda\\) is the wavelength of the light,
+* \\(\scriptsize  c_0\\) is the speed of light in a vacuum, and
+* \\(\scriptsize  f\\) is the frequency of the light.
+
+For a medium with a refractive index of \\(\scriptsize n\\), the relationship is:
+
+$$ \frac{c_0}{n} = \frac{\lambda}{n} f $$
+
+That is to say, the speed of light and wavelength change in a medium, but the frequency remains the same.
+
+## Sources
+
+- [Wikipedia](https://en.wikipedia.org/wiki/Wavelength)
+- [Brittanica](https://www.britannica.com/science/wavelength)
+
+## See also
+- [Energy of light](/formulas/energy-of-light/)