Question 28.Q-Q.7: As an analogy to wave packets, consider an “automobile packe...

Principles of Physics A Calculus-Based Text

As an analogy to wave packets, consider an “automobile packet” that occurs near the scene of an accident on a freeway. The phase speed is analogous to the speed of individual automobiles as they move through the backup caused by the accident. The group speed can be identified as the speed of the leading edge of the packet of cars. For the automobile packet, is the group speed (a) the same as the phase speed, (b) less than the phase speed, or (c) greater than the phase speed?

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