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Need help in understanding phase angle/difference in A level physics.

  1. Feb 26, 2012 #1
    I understand what a phase angle/difference is, but when it comes to applying them in questions (from past papers) my mind draws a blank. Can anyone here in simple terms, explain how can I draw lets say a phase angle difference 'precisely' of a wave in a graph?

    Additional details : I am in AS level right now, so please go easy on any advanced mathematics. And just as a heads up: We have just learnt a sine graph in math aswell as radians( so I know a whole wavelength is 2∏.)
  2. jcsd
  3. Feb 26, 2012 #2
    I Just came across a question, which I think will help explain my doubt better

    http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_w02_qp_2.pdf

    here in question 5 it says " draw the variation with time t of the displacement x of the point in wave T2" So see, while I know phase angle of 60° means T2 lags behind T1 by 60( less than ∏/2 or 90°), I have no idea how to draw it.
  4. Feb 26, 2012 #3
    The phase of a transverse wave is how far it has been translated or shifted. Think back to algebra when we translated graphs of lines by adding and subtracting numbers.

    In this case, a phase of 60 degrees results in a shift of ∏/3 radians or 1/6 of a wavelength, being that one wavelength = 2∏ = 360 degrees. If the wavelength of this graph is 3 units then it will be shifted by .5 units to the left (T2 drags behind T1)
  5. Feb 28, 2012 #4
    Thank you elliott, no one really explained it before with translation..it was very helpful :)
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