Talk:Phase angle

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This article contains material from the Federal Standard 1037C, which, as a work of the United States Government, is in the public domain.

How about a picture or diagram?


[edit] it's nonsense

The article says:

The phase angle of a point on a periodic wave is the distance between the point and a specified reference point, expressed using an angular measure.

and

For example, in electrical engineering, sinusoidal voltage and current can be expressed as a sine function with a magnitude such as:
v(t) = V_m \cos( \omega t + \varphi ) \;
Where \varphi is the phase angle,


How do I reconcile those two statements? What is the "reference point"? And what is "the point"? Usually the reference point is t=0, and "the point" is t. The angle at t=0 is \varphi, and at t is \omega t + \varphi, so the distance between them is just ωt, which does not depend on \varphi!


Furthermore, the article says:

This angular measure is obtained by projecting a rotating vector onto the real axis of the complex plane.

Using the same example, the projection on the real axis is the voltage v, not \varphi.

--Bob K 18:00, 19 August 2007 (UTC)