[quote author=Fu-Kwun Hwang link=topic=345.msg1091#msg1091 date=1142067525]
<center><b><font size=+4>Bouncing Balls</font></b><hr><applet code="bouncing.class" width=600 height=300 codebase="/java/bouncingBall/"><param name="Reset" value="Reset"><param name="Start" value="Start"><param name="Vlabel" value="Initial Velocity="><param name="Vunit" value=" m/s"><param name="Vratio" value="Vo/Vi="><param name="Time" value="Time(s)="></applet><hr></center><p>Some balls bounce better than others.<p>A particular ball can be characterized by its<ul><b><font color="#0000FF">coefficient of restitution:</font></b></ul>The ratio of its rebound speed <b>V<sub>f </sub></b>to its collision speed<b>V<sub>i</sub></b><ul>when its bounces off a hard, stationary surface that can't move.</ul><ul><font color="#0000FF">coefficient of restitution r = V<sub>f </sub>/V<sub>i</sub></font></ul>Scientists have found that, for most balls, this speed ratio<ul>remains constant over a wide range of collision speeds.</ul>The amount of kinetic energy transformed at impact is called<ul>the <b>collision energy </b>(become thermal energy).</ul>This java applet shows you the effects due to<ul>different <i>coefficient of restitution.</i></ul><hr WIDTH="100%"><p>1. You can enter different value of <i>coefficient of restitution </i>as(Vo/Vi).<ul>Then, press <b>return</b> key to start the animation.</ul>2. You can change the initial velocity <b>Vx </b>of the ball.<ul>Click near the tip of <b><font color="#0000FF"><font size=+1>bluearrow( represent</font></font></b> its velocity)<ul>and drag it left/right.</ul></ul>3. You can change the initial height  (drag it up and down with mouseleft click)<p>4. Press <b>Start</b> button to start/restart animation.<ul>The animation will stop automatically when it bounces off the screen.</ul>4. Press <b>Reset</b> button to reset parameters to its default value.<ul>It also clear the screen.</ul>5. Press the mouse button to <b>pause</b> the animation<ul>If you click the <b>left </b>mouse button,<ul>animation will resume when you release it.</ul>If you click the <b>right</b> mouse button,<ul>you need to click it again to resume.</ul></ul>6. The mouse coordinate (X,Y) will be shown when its inside the window.<ul>You will know the timing t from (X and velocity <b>Vx</b>)</ul>

Hi, I know this is old but could anyone compile it for me...i want keep and use it offline. Thanks in advance.