What is Wave velocity: Definition and 29 Discussions

The group velocity of a wave is the velocity with which the overall envelope shape of the wave's amplitudes—known as the modulation or envelope of the wave—propagates through space.
For example, if a stone is thrown into the middle of a very still pond, a circular pattern of waves with a quiescent center appears in the water, also known as a capillary wave. The expanding ring of waves is the wave group, within which one can discern individual waves that travel faster than the group as a whole. The amplitudes of the individual waves grow as they emerge from the trailing edge of the group and diminish as they approach the leading edge of the group.

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  1. A

    Propagation Wave Expressions and Wave Velocity

    Hello everyone, I would really appreciate some help on the following problem on plane waves and propagation. Not too sure if my attempt at writing the propagation wave expressions are correct, and how to handle the arbitrary function f(u). For the velocity, the wavelength is not specified, so is...
  2. T

    Temperature and Sound Wave Velocity: Exploring the Proportional Relationship

    Apologies if this is a question with a basic answer, I'm coming back to physics after many years of being away from it! I read somewhere that for longitudinal sound waves traveling through air, if the temperature increases by 1 degree celsius then the velocity of the wave will increase y 0.6...
  3. G

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  4. Zakiyah Afrin

    What will the wave velocity be in this string?

    Homework Statement What will be the wave velocity, if a string of 100 cm length is in a 10 kg-wt tension forms 9 nodes when vibrated and becomes symphonic to a 50 Hz tuning fork. Given, Cross sectional area of string, $$A=4.95 mm^2$$ & density, $$d = 0.25 g/cc$$? Homework Equations $$...
  5. Arka sarkar

    Longitudinal Wave Velocity: Why it's Greater in Solids

    Why the velocity of longitudinal wave in solid is greater than transverse wave
  6. K

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  7. Pushoam

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  8. harini07

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  9. H Smith 94

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  10. S

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  11. Rookie

    String Wave Velocity and Tension

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  12. N

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  13. C

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  14. K

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  15. R

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    Homework Statement A transverse wave on a cord is given by D(x, t) = 0.19sin(2.9x - 35t), where D and x are in m and t is in s. 1) At t = 8.6*10^-2 s, what is the displacement of the point on the cord where x = 0.62 m? 2) At t = 8.6*10^-2 s, what is the velocity of the point on the cord...
  16. L

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    Homework Statement I'll try to translate the problem as faithfully as I can: A wave pulse moves along the positive OX axis. Its form when t=0 is f(x) = y0/[1 + (x/a)^2] Find the expression for the transverse velocity as a function of x and t. At the point x=0, what will be its max...
  17. L

    Calc group velocity and wave velocity for a wave

    Homework Statement a wave function \Psi=Aei(px-Et)/h where p is momentum and E=p2/2m calc group and wave velocityHomework Equations group vel=dw/dk wave v=w/kThe Attempt at a Solution I just have no idea what they did here to solve it. i(px-Et)/h=i(kx-wt) than somehow got k=p/h than...
  18. C

    Wave velocity in a free-hanging rope

    Homework Statement A uniform rope of length L hangs freely from the ceiling. Show that the time for a transverse wave to travel the length of the rope is t0 = 2\sqrt{L/g}. Homework Equations v = \sqrt{\tau/\mu}. (Where \tau is the tension and \mu the linear density of the rope.)...
  19. D

    Exploring Standing Wave Velocity: Human Error or Physics?

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  20. F

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  21. H

    Wave Velocity, Amplitude & Phase change

    Hi All, I am having trouble trying to understand & calculate the effects that magnetic soils have on a pulsed induction metal detector, in particular soils containing iron. I have read this: The section on Soil Magnetic Properties...
  22. E

    What is the Velocity and Acceleration of a Transverse Wave on a Stretched Cord?

    Homework Statement The left-hand end of a long horizontal stretched cord oscillates transversely in SHM with frequency f = 250 Hz and amplitude 2.6 cm. The cord is under a tension of 140 N and has a linear density \mu = 0.12 kg/m. At t = 0, the end of the cord has an upward displacement 1.6...
  23. D

    Wave velocity on a taut string

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  24. B

    Wave Velocity in Terms of Tension

    A few friends and I built a wave "machine." It's made by laying out brass "rods" about a foot long next to each other about an inch or so apart on tape, and then taping the top side. When holding both sides of this "machine," when one strikes one rod at one end, it makes the rod in front of it...
  25. B

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    Homework Statement A. A typical steel B-string in a guitar resonates in its fundamental frequency at 240 Hz. The length of the string is 0.680 m. What is the wave velocity in the string? B. The tension in the above string is 86.8 N. Calculate the mass of a 2 m long piece of the steel...
  26. L

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  27. P

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    Prof gave us this equation and question: The equation of a transverse wave traveling in a rope is: y=10sin*pi(0.01x-2.00t) He said that x and y are expressed in cm, and time in seconds. We are to: A. find the amplitude, frequency(Hz), velocity(cm) and wavelength(cm) of the wave. B...
  28. X

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  29. T

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    A sound wave of velocity 600 m/s has a wavelength of 3 m. At a certain instant one of the molecules of the medium is at its normal position. How long will it be before this same molecule is again at its normal position? v=f&lambda;, f=v/&lambda; =(600m/s)/3m = 200Hz T=1/f=1/200=.005s...
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