## Delta E values

$E=hv$

Miriam Sheetz 2B
Posts: 64
Joined: Fri Sep 28, 2018 12:25 am

### Delta E values

For V=E/h, why do we use the a positive delta E value even though it is actually negative?

Andrew Sun 1I
Posts: 30
Joined: Fri Sep 28, 2018 12:18 am

### Re: Delta E values

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.

Sameen Mahmood 3D
Posts: 37
Joined: Wed Jun 13, 2018 3:00 am

### Re: Delta E values

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!!