- #1
chingel
- 307
- 23
I was reading the derivation on Wikipedia:
http://en.wikipedia.org/wiki/Group_velocity#Derivation
Why is the first part before the integral sign ignored when calculating the velocity? Surely it would also cause a phase shift in some time interval and make the waves move forward (or backward)?
http://en.wikipedia.org/wiki/Group_velocity#Derivation
Why is the first part before the integral sign ignored when calculating the velocity? Surely it would also cause a phase shift in some time interval and make the waves move forward (or backward)?