The following simulation show two point source located at P1=(x1,y1,z) and P2=(x2,y1,z)

It only show waves moving toward a common point P=(x,y,z), so that the interference can be shown at (x,y,z)
$y1(t)=h*sin(k*r1-w*t)$ where r1 is the distance of bwtween P1 and P.
and
$y2(t)=h*sin(k*r2-w*t)$ where r2 is the distance of bwtween P2 and P.

You can change the distance between source with slider for d, location of observed point with slider for x,wavelength with slider for lambda.

Two blue arrows represent phases for those two wave at P. i.e. represent (k*r1-w*t and k*r2-w*t).

translate strings in simulation to different language format before download
Full screen applet or Problem viewing java?Add http://www.phy.ntnu.edu.tw/ to exception site list
Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop. This work is licensed under a Creative Commons Attribution 2.5 Taiwan License
Download EJS jar file(1092.9kB):double click downloaded file to run it. (68 times by 21 users) , Download EJS source View EJS source