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Why does increased tension increase the wave speed of a stationary wave?

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15goddess15 | 16:53 Sat 05th Feb 2011 | Science
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What is the physics behind the relationship?
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Ha can a stationary wave have a speed?
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Yes. Stationary here implies it does not transfer energy.
There was a programme about waves on BBC4 last week, it's repeated next week - yes indeed, sea waves go up and down but don't always move along the surface of the ocean.
Oh.
-- answer removed --
Is the tension you refer to the tension of a vibrating string or similar and do you mean frequency when you say speed. This may clarify the question if not for me but for somebody who can answer it.
jomfil is pretty close to what the questioner is describing. A transverse
wave is one in which the vibrations are perpendicular to the direction of wave motion which can be demonstrated on a tensed string attached to an oscillator. The entire experiment, inclduing the predictive mathmatical equations is found here:

http://www.niiler.com/phy130/lab11waves.pdf
On the BBC4 programme it was explained that waves travel because of (1) the water's surface tension is trying to flatten the wave, and, (2) gravity, which also tries to flatten the wave. Net result is that the wave is continually moving out from under something like a 'pressure point'. (Not very well put, but I hope you see what's meant). The higher the surface tension, the more 'pressure', and the faster the wave moves to try and get out from under it.
Generally a wave is caused where there is a disturbance in a medium and a restorative force overshoots restoring the disturbance

( Electromagnetic waves are a bit different so we'll ignore those here )

If you pluck a string on a guitar you are causing a disturbance and it is the tension of string whic is the restorative force - the more tension the stronger the force - the more force the faster the string will return to (and overshoot it's original position) so the frequency of the wave will be higher - That is the number of times a second it goes back and forth will be higher.

A bit confused - as I think are others here because normally when we talk about the speed of the wave we are talking about the speed of motion of the wave form itself which is zero for a standing wave.

I gather you mean the speed of the string as it goes back and forward. We normally refer to this by it's frequency because although it continues to go back and forward at the same number of times a second the distance it moves slowly becomes less and less as there is a "damping" effect as the string loses energy.

You can tell this because as the string is plucked the note remains the same - it doesn't get lower or higher - this is the frequency.

However it slowly gets quieter - the amplitude reduces

I don't think you're looking for a treatment in this much depth but in case I'm wrong check out this:

http://www.owlnet.ric...Files231/monocord.pdf

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