Talk:Transverse wave

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[edit] Excess

Probably an excess of 'longitudinal' material here after the merge. Charles Matthews 21:28, 20 Feb 2004 (UTC)

[edit] image

the image looks old and shitty, somebody should change it —Preceding unsigned comment added by 84.66.153.102 (talk • contribs) 11:55, 18 December 2006 (UTC)

[edit] Confusing

Confusing in second paragraph. Probably need to state that in seismology, have transverse and longitudinal waves. —Preceding unsigned comment added by 24.225.203.96 (talk • contribs) 20:34, 16 February 2006 (UTC)

[edit] Transverse waves travel slower than longitudinal waves ?

I'm not a physicist so I'm not going to edit the paragraph which states that "transverse waves travel slower than longitudinal waves". Maybe someone can expand on it though because I'm left confused by it: I thought light (an electromagnetic wave hence transverse) travels conciderably faster than sound (a longitudinal wave)!

Don't mix wave speeds for different media and different waves (electromagnetic and sound). Transverse waves travel slower than longitudinal waves in the same medium. --Berland 08:26, 12 April 2007 (UTC)

[edit] Polarization

Since mentions polarity needs a reference to polarization and perhaps the three types thereof. -Wfaxon 13:44, 4 August 2006 (UTC)

Transverse waves and polarization definitely relate. The key notion in understanding polarization is to realize that the EM transverse waves are two dimensional. The use of water waves as an example obscures this point. The string example needs to be elaborated, something like below, and needs to be referenced early in the polarization discussions.

.... By moving your hand up-and-down you can launch waves on the string. Notice though, that you can also launch waves by moving your hand side-to-side. This is an important point. There are two independent directions in which wave motion can occur. Further, if you carefully move your hand in a clockwise circle, you will launch waves that describe a left-handed helix as they propagate away. Similarly, if you move your hand in a counter-clockwise circle, a right-handed helix will form. These phenomena go beyond the kinds of waves you can create on the surface of water; in general a wave on a string can be two-dimensional. Two dimensional transverse waves exhibit a phenomenon called polarization. A wave produced by moving your hand in a line is a linearly polarized wave, a special case. A wave produced by moving your hand in a circle is a circularly polarized wave, another special case.

Electromagnetic waves behave in this same way, although it is harder to see. Electromagnetic waves are also two-dimensional transverse waves. This two-dimensional nature should not be confused with the two components of an electromagnetic wave, the electic and magnetic field components. Each of these fields, the electric and the magnetic, exhibits two-dimensional transverse wave behavior, just like the waves on a string. ....

AJim 04:16, 19 July 2007 (UTC)

[edit] Speed of logitudinal disturbance in transverse waves

Im trying to get clear in my mind the reason for the fact that longitudinal distubances in transverse waves can actually travel faster (or slower) than transverse fluctuations. Its something to do with the derivative of a function I think but could someone point me in the right direction. Do I start with the wave equation?--Light current 16:22, 16 September 2006 (UTC)

[edit] Answer for above question

You are on the right track with the wave equation. The easiest way to visualize this idea is to think about a a wave that travels on a streched string, like the pluck of a harp or the striking of a piano. The wave equation for a traveling transverse wave on a stretched string is

d²y/dx² = μ/T d²y/dt²

Where T = tension on the string and μ = mass per unit length and the wave velocity (longitudinally) = The square root of (T/μ) This equation comes from an analysis of the forces exerted on a very small length of the string as it is bent under tension.

A solution of the above differential equation gives the motion function

y(x,t) = A sin ((2π/λ) (x-vt))

where λ = wavelength of the transverse vibration and v = the longitudinal velocity This allows you to see the difference in the longitudinal velocity and the transverse velocity. The transverse speed of a propagating wave is not constant. In order to see what the maximum velocity of the transverse function is, you have to take a derivative irt time of the above function. that gives you

dy(x,t)= A (2πv/λ) cos ((2π/λ) (x-vt)

Where A2πv/λ will be your maximum velocity in the transverse direction.

The main idea is that the velocity in the transverse direction will change depending on the phase of the wave.The phase is what all the terms in the cos are equal to. When the Y = the maximum height, the velocity will = 0 because it cooresponds to a 90 degree phase. The cos of 90 degrees = 0 so velocity will equal zero. When the wave comes through the equilibrium point transversely, its at its maximum velocity on the Y axis which cooresponds to a phase of 0 degrees or 180 degrees.

The velocity on the X axis (longitudinally) will always be constant because it is determined by the qualities of the medium it is traveling. For a string, it happens to be The square root of (T/μ)

hope this helped.

Yeah its useful and a good start. THanks--Light current 12:44, 18 December 2006 (UTC)

[edit] Why does this article need cleaned up?

This article looks fine to me, can someone suggest a reason why the cleanup tag should still be applied to this page? —The preceding unsigned comment was added by 129.101.55.134 (talk) 06:19, 22 February 2007 (UTC).

various parts of the article have somewhat strange wording, repetitiveness(if that is even a word), and other small things, I edited some out, somebody else look around for similar stuff. --FranzSS 04:51, 26 April 2007 (UTC)

-->This sentence in the introduction was at best nonsensical, and at worst patently wrong: "A transverse wave has 3 nodes and 2 antinodes." Minor change, but gets my goat.--Jovial Air 21:27, 6 May 2007 (UTC)