Drag the two sliders until you feel the blue segments are in line with each other.
And red egments are in line with each other,too!

Click the show check box to find out the answer!

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(953.4kB):double click downloaded file to run it. (13 times by 11 users) , Download EJS source View EJS source