## Negative Sign

$\lambda=\frac{h}{p}$

Raymond Ko 1H
Posts: 29
Joined: Fri Sep 28, 2018 12:19 am

### Negative Sign

For the equation involving atomic levels:
En = -(hR)/n^2
Could someone explain for me one more time why there is a negative sign at the beginning of the equation?

John_Richey_4A
Posts: 69
Joined: Fri Sep 28, 2018 12:27 am

### Re: Negative Sign

Because it is energy emitted which results in an energy state more negative than when it hadn't emitted a photon.

Joonsoo Kim 4L
Posts: 61
Joined: Fri Sep 28, 2018 12:29 am

### Re: Negative Sign

The negative sign indicates that energy is lost from the electron in the process of jumping from a higher to lower energy level. The opposite of this value (positive number) would be the energy gained by the photon that is emitted as a result of this jump between energy levels.

Andrewwiner4D
Posts: 32
Joined: Fri Sep 28, 2018 12:28 am

### Re: Negative Sign

Because the electron is losing energy as it moves down energy levels. Photons will be emitted (Light will be visible).
-Andrew Winer 4D

Anita Wong 1H
Posts: 68
Joined: Fri Sep 28, 2018 12:27 am
Been upvoted: 2 times

### Re: Negative Sign

joonsoo explained it right! Because we are going from a higher energy level to a lower energy level, the change in energy is negative since we are going down energy levels.