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Waves, finding frequency, wavelength, and speed

  1. Aug 24, 2007 #1
    I am assigned the even problem for homework, but I am lost, so I found an odd problem with the same type of question and has the answer.... I just need to know how the calculations are done

    1. The problem statement, all variables and given/known data

    The displacement of a wave traveling in the negative y-direction is D(y,t)=(5.2cm)sin(5.5y+72t), where y is in m and t is in sec. Find the frequency, wavelength and speed of the wave

    2. Relevant equations

    D(x,t) = A sin[2π (x/λ -t/T) + Φ]

    3. The attempt at a solution

    I have no clue, the answers are:

    11.5 Hz
    1.14 m
    13.1 m/s
     
  2. jcsd
  3. Aug 24, 2007 #2
    Well I'll help get you started.

    By comparing the two equations, you know that

    [tex]5.5 = \frac{2\pi}{\lambda}[/tex]

    So you can easily find the wavelength.

    How can you find the frequency in a similar manner? What is the relationship between frequency and period? When you have the frequency and wavelength, what is the relationship between those and velocity?
     
  4. Aug 24, 2007 #3
    Thanks!
     
    Last edited: Aug 25, 2007
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