## Combining E=hv and c=ƛv [ENDORSED]

$E=hv$

Jose Lupian 1C
Posts: 27
Joined: Fri Apr 06, 2018 11:03 am

### Combining E=hv and c=ƛv

This past lecture Professor Lavelle showed an example where he combined E=hv and c=ƛv. This lead to the equation E=hc/ƛ. How did this combination result in this final equation?

Chem_Mod
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### Re: Combining E=hv and c=ƛv  [ENDORSED]

Solve for v and plug v into E= hv.

Isobel Tweedt 1E
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Joined: Fri Apr 06, 2018 11:05 am

### Re: Combining E=hv and c=ƛv

v = c/ƛ so E = hc/ƛ

Steven Luong 1E
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Joined: Fri Apr 06, 2018 11:03 am

### Re: Combining E=hv and c=ƛv

So we have E = hv, where h is Planck's constant and v is the frequency. We have c = ƛv where ƛ is the wavelength, c is the speed of light while v is also frequency. If we solve for v in c = ƛv we will get v = c/ƛ. Now we can plug that into E = hv where we will get E = hc/ƛ.

Elena 1H
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### Re: Combining E=hv and c=ƛv

from c=λv you solve for v and get v=c/λ. You substitute c/λ for v in the E=hv equation and get E=hc/λ

Rummel Requerme 1E
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### Re: Combining E=hv and c=ƛv

First, you solve for v in the second equation, then plug that into E=hv.

shouse1f
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### Re: Combining E=hv and c=ƛv

Will the value of c normally be given for use of the equation E=hc/ƛ?

Alexandra Albers 1D
Posts: 61
Joined: Fri Sep 28, 2018 12:18 am

### Re: Combining E=hv and c=ƛv

c is a constant, and it is likely that the value of it will be given to us in the equation sheet provided by Dr. Lavelle, but it might be useful to memorize it anyway.