Recently, my family and I went to the Strong National Museum of Play, amd I had to try and find a way to keep from being bored while my sisters were in the Bearnstein Bears room. Luckily, there was a huge pinball exhibit just next door, so I did what any sane person would do... and spent half an hour of my life staring at blinking lights and trying not to rage quit every time the ball fell between my flippers. Needless to say, fun times! Having said that though, there's actually alot of physics in pinball that can give you a slight edge.
First of all, how does the ball keep sliding back down to its inevitable doom? The answer: the slope of the table. Because the machine is on an incline, gravity will act on the ball such that it rolls towards the flippers.
Second, how can you read where the ball will go? While I doubt anybody has the time to measure out ball speed, moment of inertia of the flippers, etc., etc., by understanding the basics of momentum, you can get a general idea of the final direction the ball will move in. Because momentum is a vector quantity, by figuring out which way the ball is moving, and hitting the flipper so that where you want the ball to go is between the ball's velocity vector and the flipper's velocity vector, the ball should roughly go in the direction you want.