### Relationship with Equations

Posted:

**Sat Oct 13, 2018 6:41 pm**Can someone explain to me the relationship between the two equations E=hv and c=λv? How are they different?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=14&t=33752

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Posted: **Sat Oct 13, 2018 6:41 pm**

Can someone explain to me the relationship between the two equations E=hv and c=λv? How are they different?

Posted: **Sat Oct 13, 2018 6:59 pm**

E=hv indicates that the energy per photon is equal to Planck's constant times frequency. c=λv indicates that the speed of light is equal to the wavelength times the frequency. A possible relationship between the two equations is that you are able to solve for frequency in both and substitute it within the other equation.

Posted: **Sat Oct 13, 2018 7:12 pm**

Like the comment before noted it is good to know both equations and be able to apply them because you can go from one to the other for the needed answer. E=hv involves energy, planck’s constant, and frequency. C=hv is measuring the speed of light by multiplying planck’s constant with frequency. Make sure to remember the correct units also. It will be helpful to just have them memorized so that you can convert when necessary.