5 minutes
The Cue
The cue ball moves only because we typed its velocity into the scene file.
Where the tip lands
A cue tip meets the ball for about a millisecond, so the strike is one impulse J along the shot. Landing at height h above the centre, it gives the ball a speed of J/m and a spin of J·h/I, where I = 2/5·m·R² says how hard a ball is to turn. At h = 2/5·R that spin is exactly v/R, so the ball rolls from the first instant. Below the centre is backspin, called draw. Above it is topspin, called follow. A lone ball, struck at 2 m/s:
A lone ball never comes back. It would need a tip a whole radius below centre, so draw needs a ball to hit.
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