1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Harmonic Waves help

  1. Dec 5, 2004 #1
    Hello, I am having a problem solving part B of the following problem

    A harmonic wave moving in the positive x direction has an amplitude of 3.8 cm, a speed of 36.0 cm/s, and a wavelength of 38.0 cm.

    A) Calculate the displacement (in cm) due to the wave at x = 0.0 cm, t = 2.0 s. Assume that the displacement is zero at x = 0 and t = 0.

    B) Calculate the displacement due to the wave at x = 10.0 cm, t = 20.0 s.

    I got the answer to the first problem by using the equation
    y=A x Sin (w x t)

    f=velocity / wavelength = (.36m)/(.38m)= 0.94736

    Period (T)= 1 / F = 1/0.94736 = 1.055

    w= 2 x Pi/T = 2*pi / (1.055) = 5.9556

    x= 2.3cm

    This was fairly easy because x=0 and t=2 sec.

    But I am not sure what to do when x= 10.cm and t= 20sec

    Anybody got any tips?
  2. jcsd
  3. Dec 5, 2004 #2
    Just use the formula y=asinwt where a=38 cm
  4. Dec 5, 2004 #3


    User Avatar
    Homework Helper

    the formula for an harmonic wave

    [tex] y = A \sin (kx - \omega t) [/tex]
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook