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### Change in energy of an electron

Posted: Sat Oct 14, 2017 1:05 pm
Hi, I have two questions:

1. when we are finding the change in energy using the equations, are we finding the change in energy of only the electron? Will the change in energy be either positive or negative based on if the electron is absorbing or emitting?
2. When an electron emits a photon, will the energy of the photon always be labeled as positive?

### Re: Change in energy of an electron

Posted: Sat Oct 14, 2017 1:37 pm
Hey!

For 2) I'm pretty sure that when an electron emits a photon, the value of energy will be a positive number. Honestly, I'm not too sure about 1) myself, so if anyone else could clarify, that'd be great! Thanks!

### Re: Change in energy of an electron

Posted: Sat Oct 14, 2017 1:58 pm
The positive and negative signs only indicate whether the photon is emitted or absorbed, but the amount of energy that is used is always positive.
Hope this helps!

### Re: Change in energy of an electron  [ENDORSED]

Posted: Sat Oct 14, 2017 3:34 pm
When we're solving for the change in energy, it gives us the energy emitted by the electrons because of E (photon) - E (energy remove e-) = $E_{K}$ which is the energy of the electron emitted.