Drag line at left until you think it is align with blue line at right side.<br />Then, click show check box to find out how good your guest is.<br /><br />Click show2, then drag index n to see at what value it will meet with your prediction.<br />(the second line was calculated with snell's law <img class='tex' src="/demolab/smf/teximages/e/b/3/eb30e3b3375e403f4472359971221646.png" alt="n_1*\sin\theta_1=n_2 \sin\theta_2" /><p><applet code='users.ntnu.fkh.illusion_straightlinen_pkg.illusion_straightlinenApplet.class' codebase='ejsuser/2/' archive='ejs_illusion_straightlinen.jar' name='illusion_straightlinen8253' id='illusion_straightlinen8253' width='543' height='476' mayscript=true><param name='draggable' value='true'></applet></p><a href='ejstranslation.php?uid=1&muid=2&post=8253' target='translation'>translate strings in simulation to different language format</a> before download<br><a href='htmltag.php?code=users.ntnu.fkh.illusion_straightlinen_pkg.illusion_straightlinenApplet.class&name=illusion_straightlinen&muid=2' target='_blank'>Full screen applet</a> or <font color="#FF0000">Problem viewing java?</font><a href="http://www.java.com/en/download/help/jcp_security.xml" target="trusted">Add http://www.phy.ntnu.edu.tw/ to exception site list</a><br><b>Press the Alt key and the left mouse button to drag the applet off the browser and onto the desktop.</b> This work is licensed under a <a rel="license" href="http://creativecommons.org/licenses/by/2.5/tw/deed.en">Creative Commons Attribution 2.5 Taiwan License</a><br><a href='ntnujavazip.php?ejsuserjar=8253' title='ejs_illusion_straightlinen.jar' target='userjar'>Download EJS jar file</a>(983.2kB):double click downloaded file to run it. (2 times by 2 users) , <a href='ntnujavazip.php?ejsuserjar=8253&type=ejs' target='userjar'>Download EJS source</a> <a href='/demolab/phpBB/ejswui.php?ejsuser=ejsuser/2/users/ntnu/fkh/illusion_straightlinen.ejs' target='ejsxml'>View EJS source</a><img src='images/help.gif' onClick='showejsmsg(8253)'><img src='images/plus.gif' onClick='ejsparser(8253,"illusion_straightlinen");'><div id='ejsmsg8253'></div>