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Calculating Amplitude HELP!

  1. Sep 28, 2008 #1
    I don't know if it's possible or not but I want to calculate the amplitude of a certain frequency. I Have the value of the frequency, the energy needed to give this frequency and say I can calculate the wavelength from the given frequency.... So Is it possible to calculate the amplitude?

    Another thing could anyone please explain this simple wave equation for me and tell me how can I calculate the Amplitude (A) from it.

    x=A sin(t - k) + b

    What is t, k and b ( I found this equation on wikipedia)

  2. jcsd
  3. Sep 28, 2008 #2


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    Is this a homework problem? It would be helpful to see how the problem is worded.

    In your equation, A is the amplitude, t is a phase angle, k is an initial phase, and b is an amplitude offset.

    A more commonly used form is
    [tex]x(t)=Asin(2\pi ft+\phi)+b[/tex]
    where t now is time, f is frequency and [tex]\phi_0[/tex] is the phase offset. These equations describe oscillatory motion.
  4. Sep 29, 2008 #3
    Well Unfortunately I'm working solo - On my own - It's not a homework
    I just want a way to calculate the amplitude of the frequency
  5. Sep 29, 2008 #4


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    Well, amplitude is independent frequency. You need more information.
  6. Apr 21, 2010 #5
    As marcus said you need more information to calculate the amplitude.

    Yes the energy of the signal is related to the frequency.

    The amplitude is related to the energy by transmission impedance, not by the frequency.

    The actual energy in a wave is proportional to the integral of the square of the amplitude over half a cycle. The actual constants depending upon the type of wave.
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