"Billiards"

This applet simulates a simple two dimensional collision between two objects of equal mass.  After the applet loads, two balls will appear, a red one and a blue one.  The blue one is the "target".  Drag the red ball up or down to establish the impact parameter, b.  Then type an initial velocity between 0 and 100 in the "Vxi" field for the red ball.  Finally press the "Go" button to begin the simulation.  When the simulation is done, press "Reset" to try a new one.  Press "Stop" at any time to pause the simulation.  Press "Go" to continue.