## Calculating energy [ENDORSED]

H-Atom ($E_{n}=-\frac{hR}{n^{2}}$)

Maria Roman 1A
Posts: 30
Joined: Fri Apr 06, 2018 11:04 am

### Calculating energy

Problem 1.25 on the homework gives wavelength asking to find energy emitted by a photon. How would you calculate that?

404975170
Posts: 68
Joined: Thu Jul 27, 2017 3:00 am

### Re: Calculating energy  [ENDORSED]

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.

nelquosey
Posts: 31
Joined: Fri Apr 06, 2018 11:02 am

### Re: Calculating energy

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 :)

Andre-1H
Posts: 39
Joined: Fri Apr 06, 2018 11:01 am

### Re: Calculating energy

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)