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### Calculating energy

Posted: Sun Apr 22, 2018 12:40 am
Problem 1.25 on the homework gives wavelength asking to find energy emitted by a photon. How would you calculate that?

### Re: Calculating energy  [ENDORSED]

Posted: Sun Apr 22, 2018 10:47 am
Since you are given the wavelength you can solve for the frequency since the c in this equation is a constant c=(wavelength)(frequency). Then the Energy equation is E=h*(frequency). Since you just found frequency and h is a constant then you can solve for the energy. Or you can simply just use the equation E=hc/(wavelength) if you want to do it in one step.

### Re: Calculating energy

Posted: Sun Apr 22, 2018 11:25 am
I suggest using unit cancellation or dimensional analysis to solve questions like these. You have all the equations you need and the givens required to use simple cancellation and number crunching :)

### Re: Calculating energy

Posted: Sun Apr 22, 2018 12:08 pm
Like everyone has said, just because there is not a given equation for energy in terms of what is given doesn't mean that you can't rearrange two equations to obtain what you want. Combine the equations E=h(frequency) and c=v (frequency)