Talk:Amplitude

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Merge[edit]

It seems to me that pulse amplitude simply describes amplitude and then adds "...of a pulse". TomViza 09:47, 29 January 2007 (UTC)

Why?[edit]

Hmm, it's really not a great idea to use y to mean two different things, in one short article. Can we either have a different variable for the simple wave equation (which anyway needs its terms explained), or change the diag? cheers, JackyR 08:39, 18 February 2006 (UTC)

y stands for the amplitude and the displacement, but in the diagram they're the same thing. SURE>>>>>

"maximum disturbance"[edit]

The artical states that "Amplitude [is the] ... maximum disturbance ..." but "maximum" suggests "from peak to trough" whereas it is actually from distance from the average or centre y position to the peak OR trough (as the diagram correctly shows). Can this wording be improved without futher complicating the statement.

A disturbance is the movement of something away from its normal or optimum configuration, so the maximum distrubance is the distance from the average or centre. The peak and trough are both "disturbed" states, while for many systems the center is the equilibrium point.--Srleffler 17:33, 28 March 2006 (UTC)

Why is Photon Energy proportional to frequency, and not Amplitude ? It seems to me that when a wave disturbance is produced in any medium, the amount of force over time (hence work) would register as an increase in AMPLITUDE of the wave disturbance at that point, as opposed to an increase in FREQUENCY. So why, in electromagnetic waves such as photons, is the formula E = h * v (frequency), and amplitude has nothing to do with it  ?

This article is very verbose, can we have someone clean it up so it is more accessible to someone who just needs a quick reference?

I don't think it should be added on. It may be a similar and very short definition, but it's still different from amplitude.

-Lana Morgan

Question[edit]

hii this is jot..sorry i did t get any information about amplitude...the given information is very differant i think what type of my book information so plzz give me some detail —Preceding unsigned comment added by 122.109.55.87 (talk) 07:14, 23 March 2009 (UTC)

Please take questions to WP:Reference desk/science, this page is for improving the article. SpinningSpark 17:57, 23 March 2009 (UTC)

Peak to Peak vs. RMS[edit]

When most people refer to amplitude, they are implicitly talking about peak to peak amplitude, not rms. So I think we should mention that the term amplitude, when used without any qualifiers, is referring to peak to peak. Any comments? —Preceding unsigned comment added by 131.183.23.225 (talk) 21:21, 15 September 2009 (UTC)

That depends on your background and discipline. As an electrical engineer I would naturally think in terms of rms and seek meters that are calibrated in that way. Astronomers, on the other hand are used to dealing with semi-major axes (ie peak amplitude). Yet again, mariners will typically measure the amplitude of a swell peak-to-peak. You cannot say that amplitude without qualifiers means anything in particular without context. Unless you have a source that states otherwise. SpinningSpark 22:35, 17 September 2009 (UTC)

Electric examples[edit]

In electricity, the current meaning of amplitude concerns the voltage caracteristic of a signal.

Question : Could one speak of amplitude of the intensity caracteristic ? In this case an amplifier (see amplifier page) could be an intensity amplifier ! But in current usage an amplifier is a voltage amplifier. Any ideas ?

--Mario CUSENZA (talk) 10:14, 9 April 2010 (UTC)

Electrical science does not in any way limit the meaning of amplitude to voltage. One can equally speak of current amplitude or electric field intensity amplitude. Likewise, it is perfectly possible to have a current amplifier, or a power amplifier. Not sure what you have in mind with "intensity amplifier" though. SpinningSpark 11:42, 9 April 2010 (UTC)
OK, the doubt came from the amplifier article which says an amplifier increases the amplitude of a signal. The right sentence would be "an amplifier increases the power of a signal". Would it be voltage amplitude, current amplitude or both of them.--Mario CUSENZA (talk) 16:44, 10 April 2010 (UTC)

Anti-climax[edit]

"Semi-amplitude...is important in the search for exoplanets."

True or not, this is out of place, given that this is the only application that is exemplified. It makes the article read more like a wiki than an encyclopedia. 67.9.166.98 (talk) 05:55, 20 June 2010 (UTC)

I don't understand your point. Are you saying that one should not quote single examples? SpinningSpark 11:00, 20 June 2010 (UTC)

Sound wave Example[edit]

Is the amplitude of a sound wave the difference between its equilibrium pressure and the local pressure within the oscillation? From what I remember, I was always taught that the amplitude of any wave is the distance that a PARTICLE is displaced while the wave is passing. Just wanted to confirm. —Preceding unsigned comment added by 72.73.162.32 (talk) 07:03, 27 July 2010 (UTC)

Equation displacement x = A*sin(t-k) + b missing an omega?[edit]

(in "Formal Representation" section) Surely it should be A*sin(ωt-k) + b ? Harveybrown51 (talk) 19:19, 3 December 2011 (UTC)

Agreed, although it should be A*sin(ω(t-k)) + b if k is to be the time offset as stated in the article (rather than phase offset). It would also be clearer if t0 and x0 where used instead of k and b, and b were taken over to the lhs. SpinningSpark 23:23, 5 December 2011 (UTC)