# In-Phase and Out-Phase

1. May 8, 2004

### Antonio Lao

Given a traveling wave $W=Asin(\omega t + \phi)$, where A is the amplitude, $\omega$ is the angular frequnecy, t is the time variable, and $\phi$ is the phase angle.

For two waves of the same properties and traveling in the same direction, the waves vanish if the phase angle is 180 degrees. The amplitudes are doubled if the phase angle is zero or 360 degrees.

For two waves of the same properties and traveling in opposite directions, the waves formed standing waves if the phase angle is 180 degrees. What happens when the phase angle is zero or 360 degrees?

2. May 8, 2004

### Russell E. Rierson

http://www.gmi.edu/~drussell/Demos/superposition/superposition.html

3. May 8, 2004

### Antonio Lao

Russell,

Thanks. But I still can't see where the phase angle fit into the overall picture of the wave whether travelling or standing.

4. May 8, 2004

5. May 8, 2004

### Russell E. Rierson

Another Standing Wave Tutorial:

http://hypertextbook.com/physics/waves/standing/index.shtml

Last edited: May 8, 2004
6. May 9, 2004

### Antonio Lao

Russell,

Thanks. These are more than what I can chew in one setting. I have to take sometime going through the details. Again, thank you for your overwhelming response.