Difference between Group and phase velocity

Thread starter ajeet mishra
Start date Feb 4, 2016
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Difference Group Phase Phase velocity Velocity

AI Thread Summary

Phase velocity refers to the speed at which a wave phase propagates in space, calculated as the ratio of angular frequency (ω) to wave number (κ). In contrast, group velocity represents the speed at which the overall envelope of a wave packet or group of waves travels, determined by the derivative of angular frequency with respect to wave number (dω/dκ). The key distinction lies in their physical interpretations: phase velocity applies to individual wave components, while group velocity pertains to the collective behavior of wave packets. Understanding this difference is crucial for analyzing wave phenomena in various fields, including physics and engineering. The discussion concludes with acknowledgment of helpful animations that clarify these concepts.

Feb 4, 2016

ajeet mishra

Hi! I am having problem in understanding the difference between phase and group velocity clearly. In my textbook phase velocity is given by ω/κ while group velocity is by dω/dκ. What is the difference between these two terms?
Thank you!

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Feb 4, 2016

blue_leaf77

Science Advisor

There are some interesting animations on this subject:

Feb 5, 2016

ajeet mishra

thanks I have got it

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