updated 1 august 2015

amplitude of wave = 0.20 m, maximum displacement from equilibrium position
author: Andrew Duffy, lookang, tina
author EJS: Francisco Esquembre

Ejs Open Source Wave Representations Model Java Applet Simulation
« on: Today at 12:00:34 am »
Ejs Open Source Wave Representations Model Java Applet Simulation by Andrew Duffy, remixed by lookang
simulation applet hosted by NTNUJAVA Virtual Physics Laboratory
Enjoy the fun of physics with simulations!
http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2178.0
http://www.compadre.org/osp/items/detail.cfm?ID=7618&S=2
The Ejs Wave Representations model displays two representations of a sinusoidal wave on a string. One shows a movie of the wave traveling along a string  you can think of this representation as a sequence of photographs. The second 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. You can modify this simulation if you have Ejs installed by rightclicking within the plot and selecting "Open Ejs Model" from the popup menu item.
Wave representations by Andrew Duffy
In this simulation, you have two representations of wave motion to work with. One shows a movie of the wave traveling along a string  you can think of this representation as a sequence of photographs. The second 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.
Activities by Andrew Duffy
Keep pressing the "Get a new wave" button until you have a wave you are happy with. Then, play the simulation until you have a nice position versus time graph. Then, pause the simulation so that you have a photograph of the string as well as your position vs. time graph to work with. For each parameter below, figure out which of the two representations you need to determine the value of the parameter, and then find the value. 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.
and now!! frequency // remix by lookang
and Phase lead of blue point x1 to green point x2 // remix by lookang
changes made:
fixed the " with ' which is giving some error message in Ejs 4.3.3
re arrange to usual layout and color scheme
made the 2 x1 and x2 points draggable to improve usability
made feedback immediate, improve user experience
added frequency = 1/T
added phase lead of x1 to x2 = (xval2xval)/lambda*2*Math.PI;
work in progress
done!
enjoy!
suggested answers methods
screenshot of possible way to solve this great simulation by Andrew Duffy, remixd by lookang!
some definitions by
http://miniphysics.blogspot.com/2011/01/propertiesofwaves.html
Amplitude
Amplitude is the maximum displacement from the rest or central position, in either directions.
SI unit is metre
Scalar quantity
Frequency
Frequency (f) is defined as the number of complete waves produced per unit time.
SI unit is hertz (Hz)  1 Hz = 1 complete cycle per second
Scalar quantity
Determined by the source (for water waves)
Wavelength
Wavelength (λ) is the distance between corresponding points of two consecutive waves.
SI unit is metre
Scalar quantity
Speed
Speed of the wave propagation is defined as the distance travelled by a wave per unit time.
SI unit is metre per second (m s1)
Scalar quantity
Period
Period (T) is defined as the time taken to produce one complete wave.
SI unit is second (s)
Scalar quantity
T = 1/f
Velocity
Velocity is the distance travelled by a wave in one second.
SI unit is metres per second (m s1)
Vector quantity
v = fλ