Topics

Progressive waves
Transverse and longitudinal waves
Determination of frequency and wavelength
Stationary waves

Description


In this Wave representations simulation, you have two representations of wave motion to work with. The left one shows a movie of the wave traveling along a string - you can think of this representation as a sequence of photographs. The second right representation is a plot of the displacement as a function of time for two points on the string (you can select which two points to use). Using only these two representations, you can determine the values of many different parameters that describe the wave by changing the slider values or input fields. Hints have also been designed in for ease of visualizing the meaning of these parameters.

Play with the Wave Representations Model. Test what you've learned by exploring the amplitudes, wavelengths, periods, angular frequency, frequencies,  wave velocities, maximum transverse velocity (linking to simple harmonic motion) and phase difference.

Sample Learning Goals

(a) show an understanding and use the terms displacement, amplitude, phase difference, period,
frequency, wavelength and speed
(b) deduce, from the definitions of speed, frequency and wavelength, the equation v = fλ
(c) recall and use the equation v = fλ
(f) analyse and interpret graphical representations of transverse and longitudinal waves
(c) SHM: understand and use the terms amplitude, period, frequency, angular frequency and phase difference and express the period in terms of both frequency and angular frequency

Activities

Reset the simulation to get a new random wave you are happy with.
Amplitude, A and wavelength, λ  can be determined using the left graph of displacement versus position.
Then, play the simulation until you have a nice position versus time graph. Period, T and angular frequency, ω and frequency, f and phase difference between x1 and x2,  φ using the relationship φ/(2π) = t/T, where t is the time difference between x1 and x2, can be determined using the right graph of displacement of x1 and x2 versus time.

Using both graphs, it is possible to determine wave velocity v = f λ, maximum transverse speed of a single point on the string, vmax=  A ω. You can check your answers as many times as you want. The amplitude. The wavelength. The period. The angular frequency. The wave speed. The maximum transverse speed of a single point on the string.

Version:

  1. http://weelookang.blogspot.sg/2015/08/ejss-wave-representation-model.html
  2. http://weelookang.blogspot.sg/2011/04/ejs-open-source-wave-representations.html
  3. http://iwant2study.org/lookangejss/04waves_12generalwaves/ejs/ejs_model_Wave_representations_v5.jar