This java applet show you how to use the law of reflection and trigonometry in playing pool. A ball bouncing off the bank of a pool table behaves like a light ray reflecting off a mirror. There are two colored balls; red is the cue ball and blue is just an ordinary pool ball.

How to play:

• Set up an initial velocity for the red ball. To do this:
• Click LEFT mouse button within the red ball and drag the mouse back.
• Set the initial velocity for the red ball (The further back the higher the velocity.)
• The ball starts to move when you release the mouse button.
• Watch the red ball knock the blue one into one of the six pockets.
• Click the RIGHT mouse button to change the initial position for the red ball.

Try it and experiment with the trigonometry and physics behind the game.

The ShowPaths button will show the ball paths. When there is a collision the black line shows the velocity vector of each ball (watch it get shorter ... friction).

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