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Delta E values

Posted: Fri Oct 12, 2018 1:31 pm
by Miriam Sheetz 2B
For V=E/h, why do we use the a positive delta E value even though it is actually negative?

Re: Delta E values

Posted: Fri Oct 12, 2018 1:35 pm
by Andrew Sun 1I
Yes, when the original calculation gives a negative value it just signifies that there was a negative change overall, but you can't have negative energy. The negative sign is just there for conceptual understanding.

Re: Delta E values

Posted: Fri Oct 12, 2018 2:09 pm
by Sameen Mahmood 3D
For the equation E=hv, you're trying to calculate the energy of a photon. The energy of an emitted photon can never be negative, that just doesn't make sense. When we discuss a negative delta E we're talking about a loss of energy. That equation doesn't deal with energy change; the equation E=(-hR)/n^2 does. That's where a negative E is permitted, because when electrons lose energy their energy in essence becomes "more negative". I hope that helped!!